Patent Publication Number: US-2022216073-A1

Title: Processing module and processing method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-001650, filed on Jan. 7, 2021, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a processing module and a processing method. 
     BACKGROUND 
     As a processing module that processes a substrate (hereinafter, also referred to as a “wafer”) in a substrate processing system, a processing module in which wafers are simultaneously processed in one processing container is known (Patent Document 1). 
     PRIOR ART DOCUMENT 
     [Patent Document] 
     
         
         Patent Document 1: Japanese Laid-Open Patent Publication No. 2019-220509 
       
    
     SUMMARY 
     According to one embodiment of the present disclosure, there is provided a processing module. The processing module includes: a processing container including therein processing spaces in which stages are disposed, respectively, wherein a center of each of the processing spaces is located on a same circumference in the processing container in a plan view; a rotation arm including holders configured to hold wafers, which are placed on the stages of the processing spaces, respectively, wherein the rotation arm is rotatable around a center of the circumference as a rotation axis; and a sensor located between adjacent processing spaces among the processing spaces and configured to detect positions of the wafers held by the rotation arm during rotational operation of the rotation arm. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure. 
         FIG. 1  is a schematic plan view illustrating an example of a configuration of a substrate processing system in an embodiment of the present disclosure. 
         FIG. 2  is an exploded perspective view illustrating an example of a configuration of a substrate processing apparatus in the present embodiment. 
         FIG. 3  is a view illustrating an example of a positional relationship between processing spaces and a rotation arm at a standby position. 
         FIG. 4  is a view illustrating an example of a positional relationship between the processing spaces and the rotation arm at a wafer holding position. 
         FIG. 5  is a view illustrating an example of wafer movement paths in the substrate processing apparatus in the present embodiment. 
         FIG. 6  is a view illustrating an example of arrangement positions of sensors. 
         FIG. 7  is a view illustrating an example of exhaust routes of the substrate processing apparatus in the present embodiment. 
         FIG. 8  is a schematic cross-sectional view illustrating an example of a configuration of the substrate processing apparatus in the present embodiment. 
         FIG. 9  is a flowchart illustrating a processing procedure executed by the substrate processing apparatus in the present embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, systems, and components have not been described in detail so as not to unnecessarily obscure aspects of the various embodiments. 
     Hereinafter, embodiments of a processing module and a processing method disclosed herein will be described in detail with reference to the drawings. The technology disclosed herein is not limited by the following embodiments. 
     In a processing module in which the wafers are processed simultaneously in one processing container, processing spaces may be provided in the processing container, and different processes may be performed on the wafers in two or more of the processing spaces. In such a case, in the processing module, the wafers are transferred between two or more processing spaces. The wafer transfer between the two or more processing spaces is generally performed using a wafer transfer mechanism that carries the wafers into and out of the processing container. Therefore, the transfer process by the wafer transfer mechanism may be complicated. 
     Meanwhile, a technique may be conceived in which a rotation arm is installed in the processing container and substrates are transferred between two or more processing spaces by the rotation arm. However, when transferring the wafers by the rotation arm in the processing container, the positions of the wafers may be deviated from predetermined reference positions (e.g., the centers of processing spaces of a transfer destination or the like) due to positional deviation, vibration of the rotation arm, or the like during wafer delivery. The positional deviation of the wafers is a factor that reduces the uniformity of wafer processing. Therefore, it is expected to detect the positional deviation of wafers during transfer in the processing container. 
     Embodiment 
     [Configuration of Substrate Processing System] 
       FIG. 1  is a schematic plan view illustrating an example of a configuration of a substrate processing system in an embodiment of the present disclosure. The substrate processing system  1  illustrated in  FIG. 1  includes carry-in/out ports  11 , a carry-in/out module  12 , vacuum transfer modules  13   a  and  13   b , and substrate processing apparatuses  2 ,  2   a  and  2   b . Referring to  FIG. 1 , a description is made assuming that the X direction is the left-right direction, the Y direction is the front-rear direction, the Z direction is the up-down direction (height direction), and the carry-in/out ports  11  are located at the front side in the front-rear direction. The carry-in/out ports  11  are connected to the front side of the carry-in/out module  12 , and the vacuum transport module  13   a  is connected to the rear side of the carry-in/out module  12  in the front-rear direction. 
     Carriers, which are transport containers containing target substrates, are placed on the carry-in/out ports  11 , respectively. The substrates are wafers W, which are circular substrates having a diameter of, for example, 300 mm. The carry-in/out module  12  is a module configured to perform carry-in/out of the wafers W between the carriers and the vacuum transport module  13   a . The carry-in/out module  12  includes a normal-pressure transfer chamber  121  in which the wafers W are delivered to and from the carriers in a normal-pressure atmosphere by a transfer mechanism  120 , and a load-lock chamber  122  configured to switch the atmosphere in which the wafers W are placed between the normal-pressure atmosphere and the vacuum atmosphere. 
     The vacuum transfer modules  13   a  and  13   b  have vacuum transfer chambers  14   a  and  14   b , respectively, in which a vacuum atmosphere is formed. Substrate transfer mechanisms  15   a  and  15   b  are disposed inside the vacuum transfer chambers  14   a  and  14   b , respectively. Between the vacuum transfer module  13   a  and the vacuum transfer module  13   b , a path  16  in which the delivery of the wafer W is performed between the vacuum transfer modules  13   a  and  13   b  is disposed. Each of the vacuum transfer chambers  14   a  and  14   b  is formed in, for example, a rectangular shape in a plan view. Among the four side walls of the vacuum transfer chamber  14   a , the substrate processing apparatuses  2  and  2   b  are connected to the sides facing each other in the left-right direction. Among the four side walls of the vacuum transfer chamber  14   b , the substrate processing apparatuses  2   a  and  2   b  are connected to the sides facing each other in the left-right direction, respectively. 
     Among the four side walls of the vacuum transfer chamber  14   a , the load-lock chamber  122  installed in the carry-in/out module  12  is connected to the front side. Gate valves G are arranged between the normal-pressure transfer chamber  121  and the load-lock chamber  122 , between the load-lock chamber  122  and the vacuum transfer module  13   a , and between the vacuum transfer modules  13   a  and  13   b  and the substrate processing apparatuses  2 ,  2   a , and  2   b . The gate valves G open and close the carry-in/out ports of the wafer W, which are provided in mutually connected modules, respectively. 
     The substrate transfer mechanism  15   a  transfers the wafers W among the carry-in/out module  12 , the substrate processing apparatuses  2  and  2   b , and the path  16  in a vacuum atmosphere. In addition, the substrate transfer mechanism  15   b  transfers the wafers W between the path  16  and the substrate processing apparatuses  2   a  and  2   b  in a vacuum atmosphere. Each substrate transfer mechanism  15   a  or  15   b  is configured as an articulated arm, and includes a substrate holder configured to hold the wafer W. Each substrate processing apparatus  2 ,  2   a , or  2   b  collectively processes the wafers W (e.g., two or four) using a process gas in a vacuum atmosphere. Therefore, the substrate holder of each substrate transfer mechanism  15   a  or  15   b  is configured to be capable of simultaneously holding, for example, two wafers W to collectively deliver two wafers W to the substrate processing apparatus  2 ,  2   a , or  2   b . In each substrate processing apparatus  2  or  2   a , the wafers W received from stages located at the vacuum transfer module  13   a  or  13   b  side can be transferred to the stages located at the inner side by the rotation arm provided inside the substrate processing apparatus. In addition, the substrate processing apparatus  2  or  2   a  may detect the positions of the wafers W by a sensor provided therein during transfer of the wafers W by the rotation arm. 
     The pitch of the stages in the Y direction (row interval) is a pitch Py that is common to the substrate processing apparatuses  2 ,  2   a , and  2   b . Thus, the substrate processing apparatuses  2 ,  2   a , and  2   b  can be connected to any locations of the sides of the vacuum transfer modules  13   a  and  13   b , the sides being opposite to each other in the left-right direction. In the example of  FIG. 1 , the substrate processing apparatus  2  and the substrate processing apparatus  2   b  are connected to the vacuum transfer module  13   a , and the substrate processing apparatus  2   a  and the substrate processing apparatus  2   b  are connected to the vacuum transfer module  13   b . The substrate processing apparatus  2  and the substrate processing apparatus  2   a  differ from each other in the diameter of a reactor (a processing container) including a processing space corresponding to one stage according to a process application, and thus have different pitches Px 1  and Px 2 , which are pitches of the stages in the X direction (column interval). In the substrate processing apparatus  2   a , the pitch Px 2  has the same value as the pitch Py. That is, the pitch Py corresponds to the size of the largest reactor. That is, since the size of the reactor of the substrate processing apparatus  2  is smaller than that of the substrate processing apparatus  2   a , the pitch Px 1  may be set to be smaller than the pitch Px 2 . 
     The substrate processing apparatus  2   b  is a type of substrate processing apparatus having two stages and is configured such that wafer transfer is not performed in the substrate processing apparatus  2   b , and that two wafers are simultaneously carried in to be processed and then simultaneously carried out. 
     The substrate processing system  1  has a controller  8 . The controller  8  is, for example, a computer including a processor, a storage part, an input device, a display device, and the like. The controller  8  controls each part of the substrate processing system  1 . With the controller  8 , an operator may perform a command input operation or the like using the input device in order to manage the substrate processing system  1 . In addition, in the controller  8 , the operating state of the substrate processing system  1  may be visualized and displayed by the display device. In addition, the storage part of the controller  8  stores a control program, recipe data, and the like used by the processor to control various processes executed by the substrate processing system  1 . The processor of the controller  8  executes the control program to control each part of the substrate processing system  1  according to the recipe data, whereby desired substrate processing is executed in the substrate processing system  1 . 
     [Configuration of Substrate Processing Apparatus] 
     Next, an example in which the substrate processing apparatuses  2  and  2   a  are applied to, for example, a film forming apparatus that performs a plasma chemical vapor deposition (CVD) process on wafers W will be described with reference to  FIGS. 2 to 8 .  FIG. 2  is an exploded perspective view illustrating an example of a configuration of a substrate processing apparatus in the present embodiment. The internal configuration of the substrate processing apparatus  2   a  is basically the same as that of the substrate processing apparatus  2 , except for the fact that the pitch Px 2  is different from the pitch Px 1  and the arrangement positions of sensors capable of detecting the positions of wafers W. Therefore, in the following, the description of the substrate processing apparatus  2   a  that overlaps that of the substrate processing apparatus  2  will be omitted, and the substrate processing apparatus  2  will be described as a representative example. The substrate processing apparatuses  2  and  2   a  are examples of processing modules. 
     As illustrated in  FIG. 2 , the substrate processing apparatus  2  includes a processing container (a vacuum container)  20  having a rectangular shape in a plan view. The processing container  20  is configured to maintain the interior thereof in a vacuum atmosphere. The processing container  20  is configured by closing the top open portion with a gas supply part  4  and a manifold  36  to be described later. In  FIG. 2 , internal partition walls and the like are omitted such that the relationship between the processing spaces S 1  to S 4  and the rotation arm  3  can be easily understood. The processing container  20  includes two carry-in/out port ports  21  formed in the side surface thereof connected to the vacuum transfer chamber  14   a  or  14   b  to be arranged in the Y direction. The carry-in/out ports  21  are opened and closed by the gate valves G. 
     Processing spaces S 1  to S 4  are provided inside the processing container  20 . A stage  22  is arranged in each of the processing spaces S 1  to S 4 . The stage  22  is movable in the vertical direction to move upward when a wafer W is processed and to move downward when a wafer W is transferred. Under the processing spaces S 1  to S 4 , a transfer space T is provided which connects the processing spaces S 1  to S 4  and through which wafers W are transferred by the rotation arm  3 . In addition, the transfer space T under the processing spaces S 1  and S 2  is connected to each carry-in/out port  21  so that carry-in/out of wafers W is performed between the vacuum transfer chambers  14   a  and  14   b  by the substrate transfer mechanisms  15   a  and  15   b.    
     The respective centers of the processing spaces S 1  to S 4  are located on the same circumference C. The center of the circumference C coincides with the center of the substrate processing apparatus  2 , namely, the center of the processing container  20 . That is, when viewed from the top side, the respective centers of the processing spaces S 1  to S 4  are arranged on the circumference C, the center of which coincides with the center of the processing container  20 . 
     The stages  22  of the processing spaces S 1  to S 4  are laid out in 2 rows and 2 columns when viewed from the top side. The layout has different dimensions for row and column intervals. That is, when comparing the pitch Py in the Y-direction pitch of the stages  22  (row interval) and the pitch Px 1  in the X-direction pitch (column interval), the pitch Py&gt;the pitch Px 1 . 
       FIG. 3  is a view illustrating an example of a positional relationship between the processing spaces and the rotation arm at a standby position.  FIG. 4  is a view illustrating an example of a positional relationship between the processing spaces and the rotation arm at a wafer holding position. As illustrated in  FIGS. 3 and 4 , the rotation arm  3  includes four end effectors  32  capable of holding wafers W to be placed on the stages  22 , respectively, and a base member  33  having a rotation axis located at the center position of the circumference C, and is provided to be rotatable about the center of the circumference C as a rotation axis. The four end effectors  32  are connected to the base member  33  to form an X shape. The X shape of the rotation arm  3  has a configuration in which the dimension in the Y direction corresponding to the row interval of the X shape and the dimension in the X direction corresponding to the column interval of the X shape differ from each other at the wafer W holding position illustrated in  FIG. 4 . 
     By being located among respective processing spaces S 1  to S 4  at the standby position illustrated in  FIG. 3 , the rotation arm  3  does not hinder the vertical movement of each stage  22 .  FIG. 3  illustrates the state in which the wafer W is placed on each stage  22 . A description will be made of the movement of the rotation arm  3  when the wafers are transferred such that the wafers W in the first column and the wafers W in the second column are interchanged from this state, that is, when the wafers W in the processing spaces S 1  and S 2  are transferred to the processing spaces S 3  and S 4 , and the wafers W in the processing spaces S 3  and S 4  are transferred to the processing spaces S 1  and S 2 . 
     First, respective stage  22  are moved to delivery positions in the transfer space T at the lower side, and lift pins  26  provided on respective stages  22  to be described later are raised to lift the wafers W. Next, the rotation arm  3  is rotated clockwise by about 30 degrees to insert respective end effectors  32  between the stages  22  and the wafers W as illustrated in  FIG. 4 . Subsequently, the lift pins  26  are lowered to place the wafers W on respective end effectors  32 . Next, the rotation arm  3  is rotated 180 degrees clockwise to transfer the wafers W to holding positions on respective stages  22 . When the respective stages  22  raise the lift pins  26  to receive the wafers W, the rotation arm  3  is rotated counterclockwise by about 30 degrees to move to the standby position. In this way, the wafers W can be transferred by the rotation arm  3  such that the wafers W in the first column and the wafers W in the second column are interchanged with each other. As a result, for example, when different processes (e.g., a film forming process and an annealing process) are performed in the processing spaces S 1  and S 2  and the processing spaces S 3  and S 4 , respectively, the wafers W can be transferred by the rotation arm  3  between the processing spaces S 1  and S 2  and the processing spaces S 3  and S 4 . Therefore, for example, when different processes are repeated in the processing spaces S 1  and S 2  and the processing spaces S 3  and S 4  (e.g., when the film forming process and the annealing process are repeated), the time related to the transfer of the wafers W is shortened. 
       FIG. 5  is a view illustrating an example of wafer movement paths in the substrate processing apparatus in the present embodiment.  FIG. 5  illustrates the movement paths when the wafers W are transferred from the vacuum transfer chamber  14   a  to the interior of the substrate processing apparatus  2 . First, by the substrate transfer mechanism  15   a  of the vacuum transfer chamber  14   a , as illustrated by the paths F 1 , at the delivery positions of the transfer space T under the processing spaces S 1  and S 2  corresponding to the stages  22  in the same column, two wafers W are simultaneously carried into respective stages  22 . The respective stages  22  of the processing spaces S 1  and S 2  raise the lift pins  26  to receive the wafers W. 
     Next, the rotation arm  3  is rotated clockwise from the standby position by about 30 degrees, the end effectors  32  are inserted between the wafers W and the stages  22  located at the delivery positions under the processing spaces S 1  and S 2 , respectively, and the lift pins  26  are lowered to place the wafers W on the respective end effectors  32 . After the wafers W are placed, the rotation arm  3  is rotated clockwise by 180 degrees as illustrated by a path F 2  to transfer the wafers W onto the stages  22  located at the delivery positions (the holing positions of the rotation arm  3 ) of the transfer space T under the processing spaces S 3  and S 4 . The stages  22  located at the delivery positions under the processing spaces S 3  and S 4  raise the lift pins  26  to receive the wafers W, respectively, and then the rotation arm  3  is rotated counterclockwise by about 30 degrees to move to the standby position. In this state, the wafers W are not placed on the stages  22  of the processing spaces S 1  and S 2 , and the wafers W are placed on the stages  22  of the processing spaces S 3  and S 4 . Subsequently, as illustrated by the paths F 1 , two wafers W are simultaneously carried into respective stages  22  at the delivery positions located under the processing spaces S 1  and S 2  by the substrate transfer mechanism  15   a  of the vacuum transfer chamber  14   a , and the wafers W are placed on the stages  22  of the processing spaces S 1  and S 2 , whereby the wafers W are placed on all of the stages  22  of the processing spaces S 1  to S 4 , respectively. 
     Similarly, during carry-out, the wafers W placed on the stages  22  located at the delivery positions under the processing spaces S 1  and S 2  are first carried out to the vacuum transfer chamber  14   a  by the substrate transfer mechanism  15   a . Next, the wafers W placed on the stages  22  located at the delivery positions under the processing spaces S 3  and S 4  are transferred by the rotation arm  3  to the stages  22  located at the delivery positions under the processing spaces S 1  and S 2 . Subsequently, the wafers W placed on the stages  22  located at the delivery positions under the processing spaces S 1  and S 2  are carried out to the vacuum transfer chamber  14   a  by the substrate transfer mechanism  15   a . In this way, by using the substrate transfer mechanism  15   a  capable of carrying in and out two wafers W at the same time and the rotation arm  3 , the wafers W can be carried into and carried out of the processing spaces S 1  to S 4 . 
     Meanwhile, when the wafers W are transferred by the rotation arm  3  in the processing container  20 , the positions of the wafers W may be deviated from predetermined reference positions (e.g., the center positions of the processing spaces S 1  to S 4  of a transfer destination or the like) due to positional deviation, vibration of the rotation arm  3 , or the like during the transfer of the wafers. The positional deviation of the wafers W becomes a factor that deteriorates the uniformity of processing in the processing spaces S 1  to S 4 . 
     Therefore, in the substrate processing apparatus  2 , the positions of the wafers W are detected during transfer of the wafers W by the rotation arm  3 . Specifically, the substrate processing apparatus  2  includes sensors located between adjacent processing spaces S 1  to S 4  and capable of detecting the positions of the wafers W held by the rotation arm  3  during rotational operation of the rotation arm  3 . In the example of  FIG. 5 , the substrate processing apparatus  2  includes a sensor  31   a  and a sensor  31   b  between the adjacent processing spaces S 1  and S 2  and between the adjacent processing spaces S 3  and S 4 , respectively. 
     Each of the sensors  31   a  and  31   b  is, for example, a set including two unit sensors, and the sensors  31   a  and  31   b  are arranged on a straight line in the X direction passing through the center of the substrate processing apparatus  2  (the processing container  20 ), namely, passing through the center position of the circumference C. The two unit sensors of each of the sensors  31   a  and  31   b  are disposed at positions on a straight line in the X direction passing through the center position of the circumference C, with an arc of the circumference C interposed therebetween. This is to reduce a detection error due to a change in positional relationship between the two unit sensors of each of the sensors  31   a  and  31   b  when the processing container  20  is thermally expanded, by setting the expansion direction of the processing container  20  due to the thermal expansion to be the same as the arrangement direction of the two unit sensors of each of the sensors  31   a  and  31   b . As the two unit sensors of each of the sensors  31   a  and  31   b , for example, an optical sensor or a millimeter wave type sensor can be used. 
     The arrangement positions of the sensors  31   a  and  31   b  are not limited to the X direction as long as the positions are on a straight line passing through the center of the substrate processing apparatus  2 . In addition, in the substrate processing apparatus  2   a  in which the pitch Py in the Y-direction pitch (row interval) of the stages  22  and the pitch Px 2  in the X-direction pitch (column interval) of the stages  22  are the same, the sensors may be disposed on a straight line in the X-direction and a straight line in the Y direction, respectively.  FIG. 6  is a view illustrating an example of arrangement positions of sensors. The substrate processing apparatus  2   a  illustrated in  FIG. 6  includes sensors  31   a  to  31   d  which are located between adjacent processing spaces S 1  and S 2 , between adjacent processing spaces S 3  and S 4 , between adjacent processing spaces S 2  and S 3 , and between adjacent processing spaces S 4  and S 1 , respectively. The sensors  31   a  and  31   b  are arranged on a straight line in the X direction passing through the center of the substrate processing apparatus  2  (the processing container  20 ), that is, the center position of the circumference C. The sensors  31   c  and  31   d  are arranged on a straight line in the Y direction passing through the center position of the circumference C. This is to reduce a detection error due to a change in positional relationship between the two unit sensors of each of the sensors  31   a  to  31   d  when the processing container  20  is thermally expanded by setting the expansion direction of the processing container  20  due to the thermal expansion to be the same as the arrangement direction of the two unit sensors of each of the sensors  31   a  to  31   d.    
     A description will be made referring back to  FIG. 5 . In the substrate processing apparatus  2 , it is possible to detect the positional deviation amount of the wafer W in the processing spaces S 1  to S 4  of a transfer destination by detecting the position of the wafer W with the sensors  31   a  and  31   b . For example, in the substrate processing apparatus  2 , the positional deviation amount of the wafer W is calculated based on the front and rear edge positions of the wafer W detected by the sensors  31   a  and  31   b  and the output result (the rotated angles of the wafer W) of an encoder (not illustrated) provided on the rotation arm  3 . The positional deviation amount of a wafer W may be calculated using, for example, a mathematical model that is capable of calculating the positional deviation amount from the front and rear edge positions of the wafer W and the rotated angle of the wafer W. 
     In the example of  FIG. 5 , the position P 24  indicates a state in which the rear edge of a wafer W passes through the sensor  31   b  when the wafer W is transferred from the processing space S 2  to the processing space S 4 , and the position P 42  indicates a state in which the rear edge of the wafer W passes the edge sensor  31   a  when the wafer W is transferred. For example, the substrate processing apparatus  2  calculates the positional deviation amount of the wafer W in the processing space S 4  of a transfer destination based on the rear edge position of the wafer W detected by the sensor  31   b  and the output result of the encoder when the rear edge of the wafer W passes through the sensor  31   b . For example, the substrate processing apparatus  2  may calculate the positional deviation amount of the wafer W in the processing space S 4  of a transfer destination based on the front edge position of the wafer W detected by the sensor  31   b  and the output result of the encoder when the front edge of the wafer W passes through the sensor  31   b . For example, the substrate processing apparatus  2  may calculate the average value of the positional deviation amount of the wafer W detected when the rear edge of the wafer W passes the sensor  31   b  and the positional deviation amount of the wafer W detected when the front edge of the wafer W passes the sensor  31   b.    
     The substrate processing apparatus  2  is capable of correcting the positional deviation of wafers W by moving the stages  22  at least in the XY plane in the processing spaces S 1  to S 4  of the transfer destination depending on the positional deviation amounts of the wafers W detected during transfer of the wafers W by the rotation arm  3 . Specifically, the substrate processing apparatus  2  may include adjustment mechanisms  700  capable of adjusting the positions of the stages  22  and may correct the positional deviation of wafers W by controlling the adjustment mechanisms  700  to move the stages  22  depending on the detected deviation amounts. That is, the substrate processing apparatus  2  adjusts positional deviation such that the wafers W are located at the centers of the processing spaces S 1  to S 4 , respectively, when the stages  22  are raised. 
     The adjustment mechanisms  700  and the sensors  31   a  and  31   b  are fixed to the outer surface of the bottom  27  (see  FIG. 8 ) of the processing container  20 . This is to suppress a change in positional relationship between the adjustment mechanisms  700  and the sensors  31   a  and  31   b  due to the thermal expansion of the processing container  20  by fixing the adjustment mechanisms  700  and the sensors  31   a  and  31   b  to the processing container  20  which is a common member. 
       FIG. 7  is a view illustrating an example of exhaust routes of the substrate processing apparatus in the present embodiment.  FIG. 7  illustrates a case in which the processing container  20  is viewed from above in the state in which the gas supply part  4  to be described later is removed. As illustrated in  FIG. 7 , a manifold  36  is arranged in the center of the substrate processing apparatus  2 . The manifold  36  includes exhaust paths  361 , which are connected to the processing spaces S 1  to S 4 , respectively. Each exhaust path  361  is connected to a hole  351  in a thrust nut  35 , which will be described later, below the center of the manifold  36 . Each exhaust path  361  is connected to an annular flow path  363  in each of guide members  362  provided above the processing spaces S 1  to S 4 . That is, the gas in the processing spaces S 1  to S 4  is exhausted to a merging exhaust port  205  to be described later via the flow path  363 , the exhaust paths  361 , and the hole  351 . 
       FIG. 8  is a view illustrating an example of a configuration of a substrate processing apparatus in the present embodiment. The cross section of  FIG. 8  corresponds to the cross section of the substrate processing apparatus  2  taken along line A-A in  FIG. 7 . Four processing spaces S 1  to S 4  are configured in the same manner as each other, and are formed between stages  22 , on each of which the wafer W is placed, and gas supply parts  4 , which are arranged to face the stages  22 , respectively. In other words, in the processing container  20 , the stage  22  and the gas supply part  4  are provided for each of the four processing spaces S 1  to S 4 .  FIG. 8  illustrates processing spaces S 1  and S 3 . Hereinafter, the processing space S 1  will be described as an example. 
     The stage  22  also serves as a lower electrode, is made of, for example, a metal or aluminum nitride (AlN) in which a metal mesh electrode is embedded, and has a flat column shape. The stage  22  is supported by a support member  23  from the bottom side. The support member  23  is formed in a cylindrical shape, extends vertically downward, and penetrates the bottom  27  of the processing container  20 . The lower end of the support member  23  is located outside the processing container  20  and connected to a rotational driving mechanism  600 . The support member  23  is rotated by the rotational driving mechanism  600 . The stage  22  is configured to be rotatable according to the rotation of the support member  23 . An adjustment mechanism  700  is provided at the lower end of the support member  23  to adjust the position and inclination of the stage  22 . The adjustment mechanism  700  is fixed to the outer surface of the bottom  27  of the processing container  20  together with the sensors  31   a  and  31   b  (see  FIG. 5 ). 
     The stage  22  is configured to be capable of being raised and lowered between a processing position and a delivery position via the support member  23  by the adjustment mechanism  700 . In  FIG. 8 , the stage  22  located at the delivery position is drawn with the solid line, and the stage  22  located at the processing position is drawn with the broken line. In addition, at the delivery position, the end effector  32  of the rotation arm  3  is inserted between the stage  22  and the wafer W and receives the wafer W from the lift pins  26 . The processing position is the position when substrate processing (e.g., a film forming process) is executed, and the delivery position is the position at which the wafer W is delivered to and from the substrate transfer mechanism  15   a  or the end effector  32 . The moving path of the wafer W held by the rotation arm  3  (e.g., the path F 2  in  FIG. 5 ) is located closer to the bottom  27  of the processing container  20  than the processing position. As a result, the wafer W can be brought closer to the sensors  31   a  and  31   b  located on the outer surface of the bottom  27  of the processing container  20  during transfer of the wafer W by the rotation arm  3 , and thus the detection accuracy of the sensors  31   a  and  31   b  can be improved. 
     A heater  24  is embedded in the stage  22 . The heater  24  heats each wafer W placed on the stage  22  to, for example, about 60 degrees C. to 600 degrees C. In addition, the stage  22  is connected to a ground potential. 
     In addition, the stage  22  is provided with pin through holes  26   a  (e.g., three), and the lift pins  26  are arranged inside these pin through holes  26   a , respectively. The pin through holes  26   a  are provided to penetrate the stage  22  from the placement surface (top surface) of the stage  22  to the rear surface (bottom surface) opposite to the placement surface. The lift pins  26  are slidably inserted into the pin through holes  26   a , respectively. The upper ends of the lift pins  26  are suspended at the placement surface sides of the pin through holes  26   a . That is, the upper ends of the lift pins  26  have a diameter larger than that of the pin through holes  26   a , and recesses having a diameter and a thickness larger than those of the upper ends of the lift pins  26  are formed at the upper ends of the pin through holes  26   a  to be capable of accommodating the upper ends of the lift pins  26 , respectively. As a result, the upper ends of the lift pins  26  are engaged with the stage  22  and suspended from the placement surface sides of the pin through holes  26   a , respectively. In addition, the lower ends of the lift pins  26  protrude from the rear surface of the stage  22  toward the bottom  27  side of the processing container  20 . 
     In the state in which the stage  22  is raised to the processing position, the upper ends of the lift pins  26  are received in the recesses at the placement sides of the pin through holes  26   a , respectively. When the stage  22  is lowered to the delivery position from this state, the lower ends of the lift pins  26  come into contact with the bottom  27  of the processing container  20  and the lift pins  26  move in the pin through holes  26   a  such that the upper ends of the lift pins  26  protrude from the placement surface of the stage  22 , as illustrated in  FIG. 8 . In this case, the lower ends of the lift pins  26  may be configured to come into contact with, for example, a lift pin contact member located on the bottom side, instead of the bottom  27  of the processing container  20 . 
     The gas supply part  4  is provided in the ceiling part of the processing container  20  and above the stage  22  via a guide member  362  made of an insulating member. The gas supply part  4  has a function as an upper electrode. The gas supply part  4  includes a lid  42 , a shower plate  43  forming a facing surface provided to face the placement surface of the stage  22 , and a gas flow chamber  44  formed between the lid  42  and the shower plate  43 . A gas supply pipe  51  is connected to the lid  42 , and gas ejection holes  45  penetrating the shower plate  43  in the thickness direction are arranged vertically and horizontally in the shower plate  43  such that the gas is ejected toward the stage  22  in a shower form. 
     Each gas supply part  4  is connected to a gas supply system  50  via a gas supply pipe  51 . The gas supply system  50  includes, for example, sources of a reaction gas (a film forming gas), a purge gas source, and a cleaning gas, which are processing gases, a pipe, a valve V, a flow rate adjuster M, and the like. The gas supply system  50  includes, for example, a cleaning gas source  53 , a reaction gas source  54 , a purge gas source  55 , valves V 1  to V 3  provided in the pipes of respective gas sources, and flow rate adjusters M 1  to M 3 . 
     The cleaning gas source  53  is connected to the cleaning gas supply path  532  via the flow rate adjuster M 1 , the valve V 1 , and a remote plasma unit (RPU)  531 . The cleaning gas supply path  532  branches into four systems at the downstream side of the RPU  531  to be connected to each gas supply pipe  51 . Valves V 11  to V 14  are provided for respective branched pipes at the downstream side of the RPU  531 , and the corresponding valves V 11  to V 14  are opened during cleaning. For convenience, only the valves V 11  and V 14  are illustrated in  FIG. 8 . 
     The reaction gas source  54  and the purge gas source  55  are connected to the gas supply path  52  via the flow rate adjusters M 2  and M 3  and the valves V 1  and V 2 , respectively. The gas supply path  52  is connected to the gas supply pipe  51  via the gas supply pipe  510 . In  FIG. 8 , the gas supply path  52  and the gas supply pipe  510  collectively illustrate respective supply paths and respective supply pipes corresponding to respective gas supply parts  4 . 
     A high-frequency power supply  41  is connected to the shower plate  43  via a matcher  40 . The shower plate  43  has a function as an upper electrode facing the stage  22 . When high-frequency power is applied between the shower plate  43 , which is the upper electrode, and the stage  22 , which is the lower electrode, it is possible to plasmatize a gas supplied from the shower plate  43  to the processing space S 1  (a reaction gas in this example) through capacitive coupling. 
     Next, the exhaust routes from the processing spaces S 1  to S 4  to the merging exhaust port  205  will be described. As illustrated in  FIGS. 7 and 8 , the exhaust routes pass through respective exhaust paths  361  from the annular flow paths  363  in respective guide members  362  provided above the processing spaces S 1  to S 4 , and then are directed to the merging exhaust port  205  via the merging portion and the hole  351  below the center of the manifold  36 . The exhaust paths  361  have, for example, a circular cross section. 
     Around each of the processing spaces S 1  to S 4 , an exhaust guide member  362  is provided to surround each of the processing spaces S 1  to S 4 . The guide member  362  is, for example, an annular body, which is provided to surround the region around a stage  22  located at the processing position while having a gap between the stage  22  and the guide member  362 . The guide member  362  is configured to form therein a flow path  363  having, for example, a rectangular vertical cross section and an annular shape in a plan view.  FIG. 7  schematically illustrates the processing spaces S 1  to S 4 , the guide members  362 , the exhaust paths  361 , and the manifold  36 . 
     The guide members  362  form slit-shaped slit exhaust ports  364 , which are open toward respective processing spaces S 1  to S 4 . In this way, the slit exhaust ports  364  are formed in the side peripheral portions of respective processing spaces S 1  to S 4  in the circumferential direction. The exhaust paths  361  are connected to the flow paths  363 , and the processing gas exhausted from the slit exhaust ports  364  is allowed to flow toward the merging portion  351  below the center of the manifold  36 . 
     As illustrated in  FIG. 7 , the set of processing spaces S 1  and S 2  and the set of processing spaces S 3  and S 4  are arranged rotationally symmetrically by 180 degrees around the manifold  36  when viewed from the top side. As a result, processing gas flow paths, which extends from respective processing spaces S 1  to S 4  to the hole  351  via the slit exhaust ports  364 , the flow paths  363  in the guide members  362 , and the exhaust paths  361 , surround the hole  351  and are formed rotationally symmetrically by 180 degrees. 
     The hole  351  is connected to the exhaust pipe  61  via the merging exhaust port  205  inside the thrust pipe  341  of a biaxial vacuum seal  34  arranged in the central portion of the processing container  20 . The exhaust pipe  61  is connected to a vacuum pump  62  forming a vacuum exhaust mechanism via a valve mechanism  7 . One vacuum pump  62  is provided in, for example, one processing container  20 . The exhaust pipes at the downstream sides of respective vacuum pumps  62  merge and are connected to, for example, a factory exhaust system. 
     The valve mechanism  7  opens and closes the processing gas flow path formed in each exhaust pipe  61  and includes, for example, a casing  71  and an opening/closing part  72 . A first opening  73  connected to the upstream side exhaust pipe  61  is formed in the top surface of the casing  71 , and a second opening  74  connected to the downstream side exhaust pipe  61  is formed in the side surface of the casing  71 . 
     The opening/closing part  72  include, for example, an opening/closing valve  721  formed to have a size that closes the first opening  73 , and a lifting mechanism  722  provided outside the casing  71  to raise and lower the opening/closing valve  721  inside the casing  71 . The opening/closing valve  721  is configured to be capable of being raised and lowered between a closing position (indicated by the alternated long and short dash line in  FIG. 8 ) for closing the first opening  73  and an opening position (indicated by the solid line in  FIG. 8 ) retracted to the side below the first and second openings  73  and  74 . When the opening/closing valve  721  is located at the closing position, the downstream end of the merging exhaust port  205  is closed, and the exhaust of the interior of the processing container  20  is stopped. In addition, when the opening/closing valve  721  is located at the opening position, the downstream end of the merging exhaust port  205  is opened and the interior of the processing container  20  is exhausted. 
     Next, the bi-axial vacuum seal  34  and the thrust nut  35  will be described. The biaxial vacuum seal  34  includes a thrust pipe  341 , bearings  342  and  344 , a rotor  343 , a main body  345 , magnetic fluid seals  346  and  347 , and a direct drive motor  348 . 
     The thrust pipe  341  is a non-rotating central shaft and receives a thrust load applied to the upper center of the substrate processing apparatus  2  via the thrust nut  35 . That is, the thrust pipe  341  receives a vacuum load applied to the central portion of the substrate processing apparatus  2  when a vacuum atmosphere is created in the processing spaces S 1  to S 4 , thereby suppressing the deformation of the upper portion of the substrate processing apparatus  2 . The thrust pipe  341  has a hollow structure, and the interior of the thrust pipe  341  forms the merging exhaust port  205 . The top surface of the thrust pipe  341  is in contact with the bottom surface of the thrust nut  35 . In addition, the inner surface of the upper portion of the thrust pipe  341  and the outer surface of a convex portion at the inner peripheral side of the thrust nut  35  are sealed by an O-ring (not illustrated). 
     The outer peripheral side surface of the thrust nut  35  has a screw structure, and the thrust nut  35  is screwed to a partition wall of the central portion of the processing container  20 . The manifold  36  is provided above the central portion of the processing container  20 . The manifold  36 , the partition wall in the central portion of the processing container  20 , the thrust nut  35 , and the thrust pipe  341  receive the thrust load. 
     The bearing  342  is a radial bearing that holds the rotor  343  at the thrust pipe  341  side. The bearing  344  is a radial bearing that holds the rotor  343  at the main body  345  side. The rotor  343  is arranged concentrically with the thrust pipe  341  and is a rotation shaft in the center of the rotation arm  3 . In addition, the base member  33  is connected to the rotor  343 . When the rotor  343  rotates, the rotation arm  3 , that is, the end effectors  32  and the base member  33  rotate. 
     The main body  345  accommodates therein the bearings  342  and  344 , the rotor  343 , the magnetic fluid seals  346  and  347 , and the direct drive motor  348 . The magnetic fluid seals  346  and  347  are arranged at the inner peripheral side and the outer peripheral side of the rotor  343 , and seal the processing spaces S 1  to S 4  with respect to the exterior. The direct drive motor  348  is connected to the rotor  343  and drives the rotor  343 , thereby rotating the rotation arm  3 . 
     In this way, in the biaxial vacuum seal  34 , the thrust pipe  341 , which is the central axis that does not rotate on the first axis, plays the role of a gas exhaust pipe while supporting the load of the upper portion of the processing container  20 , and the rotor  343  on the second axis plays the role of rotating the rotation arm  3 . 
     [Operation of Substrate Processing Apparatus] 
     Next, the operation of the substrate processing apparatus in the embodiment will be described with reference to  FIG. 9 .  FIG. 9  is a flowchart illustrating a processing procedure executed by the substrate processing apparatus in the present embodiment. With reference to  FIG. 9 , a series of processes in which wafers W of the processing spaces S 1  and S 2 , which are first processing spaces, are transferred to the processing spaces S 3  and S 4 , which are second processing spaces, and wafer processing is performed in the processing spaces S 3  and S 4  will be described. The various processes illustrated in  FIG. 9  are mainly executed based on the control by the controller  8 . 
     First, teaching is performed to match the respective center positions of the processing spaces S 1  to S 4 , the center positions of the respective end effectors  32  of the rotation arm  3 , the center positions of the respective stages  22  of the processing spaces S 1  to S 4 , and the wafers placed on the stages  22 . In the teaching, for example, the respective center positions of the processing spaces S 1  to S 4  are set as reference positions. The reference positions are recorded, for example, in the storage part of the controller  8 . 
     Next, the wafers W located in the processing spaces S 1  and S 2  are placed on the rotation arm  3  (step S 101 ). In step S 101 , the stages  22  of the processing spaces S 1  and S 2  are moved to the delivery positions of the transfer space T at the lower side, and each stage  22  lifts the wafer W by raising the lift pin  26 . Then, the rotation arm  3  is rotated clockwise from the standby position by about 30 degrees to 45 degrees, the end effectors  32  are inserted between the stages  22  located at the transfer positions under the processing spaces S 1  and S 2  and the wafers W, respectively, and lift pins  26  are lowered to place the wafers W on the respective end effectors  32 . The rotated angle of the rotation arm  3  at this time depends on the magnitudes of the pitch Px and the pitch Py. 
     Next, the rotation of the rotation arm  3  is started, and the transfer of the wafers W from the processing spaces S 1  and S 2  to the processing spaces S 3  and S 4  is started (step S 102 ). 
     While the wafers W are being transferred from the processing spaces S 1  and S 2  to the processing spaces S 3  and S 4  by the rotation arm  3 , the positional deviation amounts of the wafers W from the reference positions are detected (step S 103 ). In step S 103 , for example, the controller  8  calculates the positional deviation amount of each wafer W based on the front and rear edge positions of the wafer W detected by the sensors  31   a  and  31   b  and the output result (the rotated angle of the wafer W) of an encoder (not illustrated) provided on the rotation arm  3 . 
     Next, the positions of the stages  22  in the processing spaces S 3  and S 4  are adjusted by moving the stages  22  in the processing spaces S 3  and S 4  of the transfer destination depending on the detected deviation amounts (step S 104 ). In step S 104 , for example, the controller  8  controls the adjustment mechanism  700  depending on the detected deviation amounts to move the stages  22  of the processing spaces S 3  and S 4  to positions where the deviation amount is canceled. As a result, the positions of the stages  22  in the processing spaces S 3  and S 4  are adjusted to be matched with the center positions of the wafers W. 
     Next, when the rotation arm  3  rotates clockwise from the processing spaces S 1  and S 2  by 180 degrees and the wafers W arrive at the processing spaces S 3  and S 4  (step S 105 ), the wafers W are delivered to the stages  22  of the processing spaces S 3  and S 4  (step S 106 ). In step S 106 , when the stages  22  located at the delivery positions under the processing spaces S 3  and S 4  receive the wafers W by raising the lift pins  26 , respectively, the rotation arm  3  is rotated counterclockwise by about 30 degrees to 45 degrees to move to the standby position. In this step, the wafers W are placed on the stages  22  of the processing spaces S 3  and S 4 , respectively. 
     Next, the positions of the stages  22  of the processing spaces S 3  and S 4  are moved to the center positions of the processing spaces S 3  and S 4  as the reference positions (step S 107 ). As a result, the positions of the wafers W on the stages  22  of the processing spaces S 3  and S 4  are adjusted to coincide with the center positions of the processing spaces S 3  and S 4  as the reference positions. 
     Next, wafer processing is performed in the processing spaces S 3  and S 4  (step S 108 ). In this way, a series of processes are completed. 
     As described above, the processing module (for example, the substrate processing apparatuses  2  and  2   a ) according to the present embodiment includes a processing container (e.g., the processing container  20 ), a rotation arm (e.g., the rotation arm  3 ), and a sensor (e.g., the sensors  31   a  to  31   d ). The processing container includes therein processing spaces (e.g., the processing spaces S 1  to S 4 ), wherein the center of each processing stage is located on the same circumference (e.g., the circumference C) and the stages (e.g., the stages  22 ) are arranged in the processing spaces, respectively. The rotation arm includes holders (e.g., the end effectors  32 ) capable of holding wafers (e.g., wafers W) to be placed on respective stages in the processing spaces and is configured to be rotatable about the center of the circumference as a rotation axis. A sensor is located between adjacent processing spaces to be capable of detecting the positions of wafers held by the rotation arm during rotational operation of the rotation arm. As a result, it is possible to detect the positional deviation of the wafers during transfer in the processing container. In addition, even when positional deviation of the wafers occurs when the wafers are transferred to a processing module by a wafer transfer mechanism (e.g., the substrate transfer mechanism  15   a  or  15   b ), such positional deviation can be detected together with the positional deviation of the wafers during transfer in the processing container. 
     In addition, the sensor according to the embodiment is a set including two unit sensors, and may be arranged on a straight line passing through the center position of the circumference. The two unit sensors may be arranged on a straight line and at positions where a circular arc of the circumference is interposed between the two unit sensors. As a result, it is possible to reduce a detection error due to a change in the positional relationship between the two unit sensors when the processing container is thermally expanded. 
     The processing module according to an embodiment may further have an adjustment mechanism configured to move the stages depending on the positional deviation amounts of the wafers calculated from the positions of the wafers detected by the sensor. This makes it possible to correct the positional deviation of the wafers during transfer in the processing container. 
     The adjustment mechanism and the sensors according to an embodiment may be fixed to the outer surface of the bottom of the processing container. This makes it possible to suppress a change in the positional relationship between the adjustment mechanism and the sensor due to thermal expansion of the processing container. 
     In addition, the stage according to an embodiment may be raised and lowered between a processing position for processing the wafers mounted on the stages and a delivery position for performing wafer delivery between the stages and the holders of the rotation arm. The moving route of the wafers held by the rotation arm may be located at a position closer to the bottom of the processing container than the processing position. This makes it possible to bring wafers closer to the sensor side during transfer of the wafers by the rotation arm so that the detection accuracy of the sensor can be improved. 
     The rotation arm according to an embodiment may transfer wafers between two or more processing spaces in which different processes are performed (e.g., between the processing spaces S 1  and S 2  and the processing spaces S 3  and S 4 ) among processing spaces. This makes it possible to shorten the length of time related to wafer transfer in the case in which different processes are repeated between two or more processing spaces. 
     In a processing method according to an embodiment, wafers located in the first processing space are placed on the rotation arm. In the processing method, the positional deviation amounts of the wafers from the reference positions while the rotation arm is rotated to transfer the wafers from the first processing space to the second processing space. In the processing method, the positions of the stages are adjusted by moving the stages arranged in the second processing space depending on the deviation amounts. In the processing method, the wafers are delivered from the rotation arm to the adjusted stages. In the processing method, the positions of the stages are moved to the center positions of the second processing spaces as the reference positions. In the processing method, wafer processing is performed in the second processing space. This makes it possible to perform wafer processing in a state in which the positional deviation of the wafers during transfer in the processing container is corrected. As a result, deterioration of processing uniformity regarding the wafers can be suppressed. 
     It should be understood that the embodiments disclosed herein are exemplary in all respects and are not restrictive. The above-described embodiments may be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended claims. 
     For example, in the embodiments described above, an example in which the substrate processing apparatus  2  or  2   a  is an apparatus that performs plasma CVD processing as substrate processing has been described, but the technique disclosed herein may be applied to any apparatus that performs other substrate processing, such as plasma etching. 
     In addition, in the above-described embodiments, the direct drive motor  348  is used as a method of driving the rotor  343  in the biaxial vacuum seal  34 , but the present disclosure is not limited thereto. For example, the rotor  343  may be provided with a pulley and may be driven using a timing bell from a motor provided outside the biaxial vacuum seal  34 . 
     According to the present disclosure, it is possible to detect positional deviation of a wafer during transfer in a processing container. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosures. Indeed, the embodiments described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the disclosures. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosures.