Abstract:
Provided is a conveyance system that adjusts the position of a conveyed substrate, prevents damage resulting from the heat of another apparatus in a conveyance base, prevents insufficient electrical power of another apparatus in the conveyance base, and can move the conveyance base smoothly. A substrate processing system is provided with a conveyance chamber and a sliding box moving within the conveyance chamber. A plurality of processing modules are connected, and the sliding box is provided with: a conveyance arm that moves wafers; a servo motor that moves the conveyance arm; and a servo motor driver that controls the electrical power supplied to the servo motor. A servo motor controller that controls the servo motor driver is disposed outside a transfer module, and the servo motor driver and servo motor controller perform optical communication.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to a movable conveyance base including a conveyance arm for moving a substrate and a conveyance system including the corresponding conveyance base. 
       BACKGROUND 
       [0002]    A substrate processing system for performing a process on a substrate, for example, a wafer for semiconductor devices (hereinafter simply called a “wafer”) includes a plurality of process modules, that is, substrate processing apparatuses for performing a process on the wafer for each sheet, thus improving processing efficiency of the wafer. 
         [0003]    The substrate processing system further includes a load lock module, that is, a carry-in/out apparatus for performing the carry-in/out of a wafer with respect to the substrate processing system, and a transfer module, that is, a conveyance system connected to the corresponding load lock module. The plurality of process modules is connected to the transfer module. The transfer module includes a slide box, that is, a conveyance base for conveying a wafer. The corresponding slide box includes a conveyance arm on which a wafer is loaded and that can extend/contract and rotate. Furthermore, the slide box moves within the transfer module and conveys the wafer between the load lock module and each of the process modules. 
         [0004]    In general, in order to efficiently locate the plurality of process modules, the transfer module includes a chamber extended in the direction in which the slide box moves. In recent years, it has been proposed to configure the transfer module using a plurality of conveyance units having a block shape and to change the length of the transfer module regarding the direction in which the slide box of the transfer module moves by changing the number of conveyance units. Accordingly, the yield of semiconductor devices or a change of a process performed on a wafer can be flexibly handled by changing the number of process modules connected to the transfer module. 
       Prior Art Documents  
       [0005]    Patent Documents 
         [0006]    Japanese Patent Application No. 2012-116851 
       SUMMARY 
       [0007]    However, as semiconductor devices that are fabricated become miniaturized, the location of a wafer for a process module needs to be adjusted with high precision. Furthermore, since the movements in two directions are performed at the same time, the amount of information about the location of the wafer transmitted from each of the sensors for detecting the location of the wafer to a servo motor controller for controlling a servo motor for a conveyance arm through optical communication means is enormous. 
         [0008]    Meanwhile, since the amount of information that may be transmitted is not much in the optical communication means, transmitted location information is limited, which makes it difficult to accurately adjust the location of the wafer. 
         [0009]    Furthermore, in general, since the inside of the transfer module communicates with the inside of each of the process modules and has been decompressed, it is difficult to dissipate heat from the slide box within the transfer module. The servo motor controller within the corresponding slide box discharges heat when generating a control signal. Furthermore, the dissipation space within the slide box is reduced because the servo motor controller partially occupies the inside of the slide box. As a result, a temperature in the slide box may rise, and there is a danger that other devices within the slide box may be damaged by the heat. 
         [0010]    Furthermore, the amount of power supplied to the slide box is limited because the slide box maintains a contactless state through the main body of the transfer module and a linear motor unit. There is a danger that power for the servo motor may be insufficient because the servo motor controller consumes power when generating a control signal. 
         [0011]    Furthermore, if the servo motor controller is disposed in the slide box, there is a danger that the slide box may not be smoothly moved by the linear motor unit because the inertia weight of the corresponding slide box is increased. 
         [0012]    One embodiment of the present disclosure provides a conveyance base and conveyance system, which are capable of preventing damage to other devices within the conveyance base attributable to heat, preventing the shortage of power for other devices within the conveyance base, and smoothly moving the conveyance base, by accurately controlling the location of a conveyed substrate. 
         [0013]    In order to solve the above-mentioned problems, according to the present disclosure, there is provided a conveyance base, including: a conveyance arm moving a substrate; a motor driving the conveyance arm; and a motor driver controlling power supplied to the motor, wherein the conveyance base moves within a conveyance chamber, a control apparatus instructing the motor driver to drive the motor is disposed at a place other than the conveyance base, and the motor driver and the control apparatus perform wireless communication. 
         [0014]    In the present disclosure, an inside of the conveyance chamber is decompressed. 
         [0015]    In order to solve the above-mentioned problems, according to the present disclosure, there is provided a conveyance system, including: a conveyance chamber; and a conveyance base moving within the conveyance chamber, wherein the conveyance system is connected to at least one processing chamber, the conveyance base comprises a conveyance arm moving a substrate, a motor driving the conveyance arm, and a motor driver controlling power supplied to the motor, a control apparatus instructing the motor driver to drive the motor is disposed at a place other than the conveyance base, and the motor driver and the control apparatus perform wireless communication. 
         [0016]    In the present disclosure, the conveyance system further includes a host computer, wherein the host computer and the control apparatus perform wired communication. 
         [0017]    In the present disclosure, the conveyance chamber includes at least one sensor detecting a location of the substrate that moves, and the at least one sensor and the control apparatus perform wired communication. 
         [0018]    In the present disclosure, the conveyance system further includes: a movement unit moving the conveyance base, and a driver of the movement unit disposed at a place other than the conveyance base, wherein the driver of the movement unit and the control apparatus perform wired communication. 
         [0019]    In the present disclosure, an inside of the conveyance chamber is decompressed. 
         [0020]    In the present disclosure, the motor driver and the control apparatus perform serial communication wirelessly. 
         [0021]    In the present disclosure, a communication rate of the serial communication is 10 Mbps or more. 
         [0022]    In the present disclosure, the wireless communication is wireless communication using radio, sound wave, or light. 
         [0023]    In accordance with the present disclosure, since the control apparatus for instructing the motor driver to drive the motor is disposed at a place other than the conveyance base in the conveyance chamber, the sensors that are disposed in the conveyance chamber and detect the location of a substrate can be connected to the control apparatus in a wired manner. Accordingly, a large amount of location information from the sensors can be transmitted to the control apparatus. As a result, the control apparatus can accurately adjust the location of a conveyed substrate because it can accurately compute the operations of the substrate in the two-axial directions at the same time based on a large amount of the location information. 
         [0024]    Furthermore, the other units of the conveyance base can be prevented from being damaged by heat because the control apparatus does not discharge heat in the conveyance base. Power for the other units of the conveyance base can be prevented from becoming insufficient because the control apparatus does not consume power in the conveyance base. The conveyance base can be smoothly moved because the inertia weight attributable to the control apparatus is not increased. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]      FIG. 1  is a plan view schematically illustrating the configuration of a substrate processing system including a conveyance system in accordance with an embodiment of the present disclosure. 
           [0026]      FIG. 2  is a perspective view illustrating a positional relationship between coil columns, feed lines, and a slide box within a conveyance unit in  FIG. 1 . 
           [0027]      FIG. 3  is a perspective view schematically illustrating the configuration of a transfer module in  FIG. 1 . 
           [0028]      FIG. 4  is a block diagram of the substrate processing system in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    Embodiments of the present disclosure are described below with reference to the accompanying drawings. 
         [0030]      FIG. 1  is a plan view schematically illustrating the configuration of a substrate processing system including a conveyance system in accordance with an embodiment of the present disclosure. Furthermore,  FIG. 1  illustrates the state in which the cover of each of the conveyance units  11  to be described later is removed, for ease of description. Furthermore, regarding  FIGS. 1 to 3 , a Y direction, an X direction, and a Z direction in the figures denote the direction in which a slide box  17  to be described later moves, a direction vertical to the direction in which the slide box  17  moves on the conveyance surface of a wafer, and the height direction of a transfer module  12  to be described later, respectively. 
         [0031]    In  FIG. 1 , the substrate processing system  10  includes the transfer module  12  (conveyance system) in which a plurality of the conveyance units  11  formed of housing-shaped chambers is connected in series, a plurality of process modules  13  connected to the respective conveyance units  11 , and two load lock modules  14  connected to one end of the transfer module  12 . 
         [0032]    In each of the conveyance units  11 , the conveyance unit  11  is inserted and disposed between two process modules  13 . The inside of each of the process modules  13  is decompressed, and plasma processing, for example, dry etching processing or film forming processing is performed on a wafer W accommodated in each of the process modules  13 . 
         [0033]    In the transfer module  12 , the insides of the respective conveyance units  11  that are connected communicate with each other, thus forming a conveyance chamber S. The inside of the corresponding conveyance chamber S is decompressed lower than atmospheric pressure by an exhaust apparatus or pressure valve (both not illustrated) included in the transfer module  12 . More specifically, the pressure within the conveyance chamber S is set to be almost identical with the pressure within each of the process modules  13 . 
         [0034]    The transfer module  12  includes a pair of coil columns  15  disposed in the direction in which the conveyance units  11  are arranged, two feed lines  16  disposed in parallel to the corresponding coil columns  15 , and the slide box  17  (conveyance base) having a parallelepiped shape disposed within the conveyance chamber S. 
         [0035]    Each of the coil columns  15  includes a plurality of coils  18  having a rectangular shape which are disposed in two columns in parallel inside the lower part of each of the conveyance units  11 . Power from the outside of the transfer module  12  is supplied to each of the coils  18 . The magnetic pole of each of the coils  18  is changed by the supply of power, thereby generating an electromagnetic force. Each of the feed lines  16  has a tubular shape, and is disposed inside the lower part of the conveyance units  11 . Each of the feed lines  16  is supplied with power from outside of the transfer module  12 . 
         [0036]      FIG. 2  is a perspective view illustrating a positional relationship between the coil columns, the feed lines, and the slide box within the conveyance units in  FIG. 1 . Furthermore, in  FIG. 2 , a conveyance arm  21  to be described later or the sidewall of the conveyance unit  11  is omitted and the slide box  17  is illustrated as being spaced apart from the bottom of the conveyance unit  11 , for a simple description. 
         [0037]    In  FIG. 2 , the slide box  17  is inserted and disposed between the pairs of coil columns  15 . A plurality of permanent magnets  19  is disposed on both sides of the slide box  17  so that they face the respective coil columns  15 . Each of the coil columns  15  and each of the permanent magnets  19  form a linear motor unit. An electromagnetic force generated by each of the coils  18  electronically drives the slide box  17  so that it moves along the coil columns  15 . The slide box  17  is pulled by the coil columns  15  because it is inserted between the pairs of coil columns  15  and is thus placed at the center of the coil columns  15  on both sides thereof. Accordingly, the slide box  17  does not come in contact with any of the coil columns  15 . Accordingly, the wafer W conveyed by the slide box  17  can be prevented from being contaminated by particles because the generation of particles, such as metal powder attributable to a contact, can be suppressed. Furthermore, the slide box  17  may be held in a guide (not illustrated) or may be raised and supported by magnet columns (not illustrated) disposed inside the sidewalls of the respective conveyance units  11 . 
         [0038]    Referring back to  FIG. 1 , the conveyance arm  21  that may be rotated and extended and contracted is included on top of the slide box  17 . A servo motor  23 , a servo motor driver  24 , and a first optical communication device  26  to be described later are included within the slide box  17 . An electricity reception transformer (not illustrated) is included on the lower part of the slide box  17 . The conveyance arm  21  loads the wafer W on a fork  20  installed at the tip thereof. The feed lines  16  supply power to the slide box  17  in a contactless manner through the electricity reception transformer. 
         [0039]    In the transfer module  12 , the carry-in/out of the wafer W with respect to each of the process modules  13  are realized by combining the movement of the slide box  17  and the rotation, contraction, and extension of the conveyance arm  21 . Furthermore, a pair of sensors  22  that are upward directed is disposed near a carrying-in port (not illustrated) of each of the process module  13  within the conveyance chamber S. The sensor  22  detects the location of the wafer W conveyed by the conveyance arm  21  and outputs information about the location of the wafer W. 
         [0040]      FIG. 3  is a perspective view schematically illustrating the configuration of the transfer module in  FIG. 1 .  FIG. 3  illustrates the state in which the inside of the transfer module  12  and the inside of the slide box  17  are shown and the conveyance arm  21  is omitted from the slide box  17 . 
         [0041]    In  FIG. 3 , the slide box  17  moving within the transfer module  12  in an arrow direction includes the servo motor  23  for driving the conveyance arm  21  with respect to a 2-axis direction, the servo motor driver  24  for controlling power supplied to the corresponding servo motor  23 , and the first optical communication device  26 . 
         [0042]    Furthermore, a second optical communication device  27  that faces the first optical communication device  26  is disposed outside the slide box  17 , more specifically, on the sidewall of the transfer module  12 . A servo motor controller  25  (control apparatus) is disposed at a place other than the slide box  17 , more specifically, outside the transfer module  12 . 
         [0043]    In the present embodiment, the servo motor driver  24  and the servo motor controller  25  exchange pieces of information using optical communication through the first optical communication device  26  and the second optical communication device  27 . Furthermore, as described above, each of the feed lines  16  supplies power to the slide box  17  in a contactless manner. That is, in the transfer module  12 , the slide box  17  does not come in contact with the housing-shaped main body of the transfer module  12  in a wired manner. Accordingly, there is no limit to the movement of the slide box  17  in the direction in which the slide box  17  moves (in the Y direction in  FIG. 3 ). 
         [0044]      FIG. 4  is a block diagram of the substrate processing system in  FIG. 1 . 
         [0045]    In  FIG. 4 , in the slide box  17 , the servo motor  23  is connected to the servo motor driver  24  through a wire, and the servo motor driver  24  is connected to the first optical communication device  26  through a wire. Furthermore, outside the slide box  17 , more specifically, outside the main body of the transfer module  12 , a host computer  28 , each of the sensors  22 , and a linear motor driver  29  (the driver of the movement unit) for controlling power supplied to each of the coils  18  of the linear motor unit are connected to the servo motor controller  25  through wires  30 , respectively. The servo motor controller  25  is connected to the second optical communication device  27  through the wire  31 . 
         [0046]    The servo motor controller  25  receives process information from the host computer  28  or information about the location of the wafer W from each of the sensors  22  through the wires  30 , that is, wired communication means. In order to properly adjust the location of the wafer W based on the pieces of information, the servo motor controller  25  generates the control signal of the servo motor  23  for driving the conveyance arm  21  or the control signal of the linear motor unit for moving the slide box  17  and sends the control signal to the servo motor driver  24  or the linear motor driver  29 . The transmission of such location information or a control signal is performed while the slide box  17  moves. Specifically, the transmission of the control signal between the servo motor controller  25  and the servo motor driver  24  is performed through optical communication means including the first optical communication device  26  and the second optical communication device  27 , for example, through serial communication having a communication rate of 10 Mbps or more. 
         [0047]    Referring back to  FIG. 1 , each of the load lock modules  14  performs the carry-in/out of the wafer W with respect to the transfer module  12  and the outside of the substrate processing system  10 . The inside of each of the load lock modules  14  is configured to be decompressed. When the wafer W is carried in from the outside of the substrate processing system  10  to the transfer module  12 , the load lock module  14  accommodates the wafer W from the container of the wafer W, for example, an FOUP, decompresses the inside thereof up to the same pressure as that of the inside of the conveyance chamber S, and transfers the wafer W to the conveyance arm  21  of the slide box  17 . Furthermore, when the wafer W is carried out from the transfer module  12  outside of the substrate processing system  10 , the load lock module  14  accommodates the wafer W from the conveyance arm  21 , raises pressure therein up to atmospheric pressure, and transfers the wafer W to the FOUP. 
         [0048]    In the substrate processing system  10 , the transfer module  12  may be extended by installing more conveyance units  11 . More specifically, the transfer module  12  is extended by connecting a new conveyance unit  11  to the end opposite the end to which the load lock module  14  of the transfer module  12  is connected and making the inside of the new conveyance unit  11  communicate with the conveyance chamber S. As in the other conveyance units  11 , a plurality of rectangular coils  18  is disposed in two columns in parallel and the two feed lines  16  are disposed inside the bottom of the new conveyance unit  11 . Accordingly, when the new conveyance unit  11  is connected to the transfer module  12 , the plurality of coils  18  of the new conveyance unit  11  elongates the pair of coil columns  15  of the transfer module  12 , and the feed lines  16  of the new conveyance unit  11  elongate the respective feed lines  16  of the transfer module  12 . 
         [0049]    Accordingly, in the substrate processing system  10 , the transfer module  12  can be easily elongated, and thus more process modules  13  connected to the conveyance units  11  can be installed. Furthermore, the transfer module  12  can be easily reduced by removing the conveyance unit  11  from the transfer module  12 , and thus the process modules  13  can be reduced in number. That is, in the substrate processing system  10 , the processing number of wafers W can be easily increased or decreased. 
         [0050]    In accordance with the conveyance system according to an embodiment of the present disclosure, the sensor  22  that is disposed within the conveyance chamber S and detects the location of the wafer W may be connected to the servo motor controller  25  through the wire  30  because the servo motor controller  25  for instructing the servo motor driver  24  to drive the servo motor  23  is disposed at a place other than the slide box  17 , more specifically, outside the transfer module  12 . Accordingly, a large amount of information about the location of the wafer W from the sensors  22  can be transmitted to the servo motor controller  25 . As a result, the servo motor controller  25  can accurately adjust the location of the wafer W that is conveyed because it can accurately compute the operations of the wafer W in two axial directions (the X direction and the Y direction) at the same time based on a large amount of the location information. 
         [0051]    Furthermore, in the aforementioned transfer module  12 , since the inside of the conveyance chamber S is decompressed, heat from the slide box  17  is not discharged to the inside of the conveyance chamber S, and the slide box  17  is heated by heat discharged by embedded units. However, the slide box  17  does not overheat because the servo motor controller  25  does not discharge heat in the slide box  17 . As a result, the servo motor  23  or the servo motor driver  24  disposed within the slide box  17  can be prevented from being damaged by heat. 
         [0052]    In the aforementioned transfer module  12 , power that may be consumed within the slide box  17  is limited because the power is supplied to the slide box  17  in a contactless manner. However, power for the servo motor  23  disposed within the slide box  17  can be prevented from becoming insufficient because the servo motor controller  25  does not consume power in the slide box  17 . 
         [0053]    Furthermore, in the aforementioned transfer module  12 , the slide box  17  is moved by the linear motor unit. The slide box  17  can be moved smoothly and accurately because the inertia weight of the slide box  17  attributable to the servo motor controller  25  is not increased. 
         [0054]    Furthermore, in the aforementioned transfer module  12 , the host computer  28  and the servo motor controller  25  perform wired communication through the wire  30 . Accordingly, the servo motor controller  25  can accurately compute the operation of the slide box  17  because it can obtain a large amount of process information from the host computer  28 . 
         [0055]    Furthermore, the linear motor driver  29  and the servo motor controller  25  perform wired communication through the wire  30 . Accordingly, the servo motor controller  25  can send a large amount of control signals to the linear motor driver  29 , and thus more accurately compute the operation of the slide box  17 . 
         [0056]    The present disclosure has been described above in connection with the embodiments, but the present disclosure is not limited to the described embodiments. 
         [0057]    In the aforementioned transfer module  12 , the servo motor driver  24  and the servo motor controller  25  are illustrated as exchanging pieces of information through optical communication. However, a communication type between the servo motor driver  24  and the servo motor controller  25  is not limited to such optical communication, and any communication not using a wire may be used. For example, radio communication or sound wave communication may be used. Specifically, high-speed serial communication may be used. 
         [0058]    Furthermore, optical communication between the servo motor driver  24  and the servo motor controller  25  is not limited to serial communication, and communication having a command level capable of a larger amount of information may be used. 
         [0059]    Furthermore, the inside of the conveyance chamber S does not need to be decompressed. For example, although the inside of the slide box  17  maintains atmospheric pressure, the present disclosure may be applied to the transfer module  12 . 
         [0060]    The place where the servo motor controller  25  is disposed is not limited to the outside of the transfer module  12 , and has only to be not disposed in the slide box  17 . In this case, in order to accurately compute the operations of the wafer W in the two axial directions at the same time, the servo motor controller  25  may be disposed at a place accessible to each of the sensors  22  through the wire  30 . Furthermore, the place where the host computer  28  is disposed is not limited to the outside of the transfer module  12 , and just must not be disposed in the slide box  17 . 
         [0061]    This application claims the benefit of Japanese Patent Application No. 2012-272534, filed on Dec. 13, 2012, in the Japan Patent Office, the disclosure of which is incorporated herein in its entirety by reference. 
       DESCRIPTION OF REFERENCE NUMERALS  
       [0000]    
       
         S: conveyance chamber 
         W: wafer 
           10 : substrate processing system 
           12 : transfer module 
           13 : process module 
           17 : slide box 
           22 : sensor 
           23 : servo motor 
           24 : servo motor driver 
           25 : servo motor controller 
           26 : first optical communication device 
           27 : second optical communication device 
           28 : host computer 
           29 : linear motor driver 
           30 : wire