Patent Publication Number: US-11664199-B2

Title: Substrate processing apparatus and substrate processing method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 10-2018-0125410, filed on Oct. 19, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND 
     1. Field 
     One or more embodiments relate to a substrate processing apparatus and a substrate processing method, and more particularly, to a substrate processing apparatus and a substrate processing method capable of improving thin film uniformity on a substrate by controlling the position of a substrate supporting apparatus. 
     2. Description of Related Art 
     As shown in  FIG.  1   , in a chamber  100  equipped with a plurality of reactors  200 , an upper portion  400  of the reactors  200  is connected to an upper wall  100   a  of the chamber  100 , and a lower portion  500  of the reactors  200  is connected to a lower wall  100   b  of the chamber  100 . The upper portion  400  and the lower portion  500  of a reactor  200  form a reaction space by face-sealing. 
     In general, the upper wall  100   a  and the lower wall  100   b  of the chamber  100  include a metal material, such as aluminum. When one side of the upper wall  100   a  of the chamber  100  includes a gas supply  2  (of  FIG.  3   ) for the reactor  200 , the upper wall  100   a  of the chamber  100  includes a heating device for heating the gas supply  2 , such as a cartridge heater (not shown in  FIG.  1   ). Through the heating device, not only the gas supply  2  but also the upper wall  100   a  of the chamber  100  is heated to a certain temperature. Therefore, the upper wall  100   a  of the chamber  100  is maintained at a higher temperature than the lower wall  100   b  of the chamber  100 . 
     In a high temperature process, thermal deformation of the chamber  100  and the reactor  200  occurs by heating a substrate supporting apparatus  300 , the upper portion  400  of the reactor  200 , and the upper wall  100   a  of the chamber  100 . However, as described above, due to a temperature difference between the upper wall  100   a  and the lower wall  100   b  of the chamber  100 , the degrees of thermal expansion or thermal deformation of the upper wall  100   a  and the lower wall  100   b  of the chamber  100  are different. As indicated by the arrows in  FIG.  1   , the upper wall  100   a  of the chamber  100  has a greater degree of thermal expansion or thermal deformation than the lower wall  100   b  thereof. 
     Further, the lower portion  500  of the reactor  200  is heated by heat conduction from the substrate supporting apparatus  300  and the upper portion  400  of the reactor but is mechanically separated from the upper portion  400  of the reactor and is not integral with the upper portion  400  of the reactor, and thus, no thermal equilibrium with the upper portion  400  of the reactor is achieved. Therefore, the heat deformation degree of the upper portion  400  and the lower portion  500  of the reactor  200  may vary. As indicated by the arrows in  FIG.  1   , the upper portion  400  of the reactor  200  has a greater degree of thermal expansion than the lower portion  500  of the reactor  200 . In addition, as shown by an arrow  600  in  FIG.  2    showing an upper surface of the chamber  100 , it can be seen that thermal expansion of the upper portion  400  of the reactor  200  is directed around the chamber  100 . 
     As such, due to a difference in thermal expansion between the upper wall  100   a  of the chamber  100  supporting the upper portion  400  of the reactor and the lower wall  100   b  of the chamber  100  supporting the lower portion  500  of the reactor  200  and a difference in thermal expansion between the upper portion  400  and the lower portion  500  of the reactor  200 , a mismatch between the upper portion  400  and the lower portion  500  of the reactor  200  occurs. 
     As a result, a mismatch between the substrate supporting apparatus  300  and components in the upper portion  400  of the reactor  200  surrounding the substrate supporting apparatus  300  occurs, and thus, a centering position of the substrate supporting apparatus  300  in the reactor  200  may be misaligned (when the center of placement of the substrate supporting apparatus in the reactor is the same as the center of a spatial symmetry in the reactor). In this case, a gas flow around a substrate becomes uneven during deposition and exhaust, and thus, the uniformity of a thin film on the substrate, in particular the uniformity of the thin film at the edge of the substrate, may become uneven or deteriorated. As a result, a defect rate of a semiconductor device may be increased, and process reproducibility between reactors may be deteriorated. 
     SUMMARY 
     One or more embodiments include a substrate processing apparatus and a substrate processing method capable of repairing the misalignment of centering of a substrate supporting apparatus according to a difference in thermal expansion between upper and lower walls of a chamber and a difference in thermal expansion between upper and lower portions of a reactor in a high temperature process and maintaining a constant gap between the substrate supporting apparatus and a gas supply control ring, thereby improving thin film uniformity on a substrate. 
     Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure. 
     According to one or more embodiments, a substrate processing method includes a first operation of moving the substrate supporting apparatus in a first direction by a first predetermined distance; a second operation of moving the substrate supporting apparatus in a second direction by a second predetermined distance; a third operation of moving the substrate supporting apparatus in the second direction by the first predetermined distance; and a fourth operation of moving the substrate supporting apparatus in the first direction by the second predetermined distance, wherein the second direction may be opposite to the first direction. 
     According to an example of the method, the method may include a fifth operation of moving the substrate supporting apparatus in a third direction by the first predetermined distance; a sixth operation of moving the substrate supporting apparatus in a fourth direction by the second predetermined distance; a seventh operation of moving the substrate supporting apparatus in the fourth direction by the first predetermined distance; and an eighth operation of moving the substrate supporting apparatus in the third direction by the second predetermined distance, wherein the fourth direction may be perpendicular to the first direction and the second direction, and may be opposite to the third direction. 
     According to an example of the method, the substrate processing apparatus may further include a ring surrounding the substrate supporting apparatus, and a gap may exist between the ring and the substrate supporting apparatus. 
     According to a further example of the method, the first predetermined distance may be greater than or equal to (an inner diameter of the ring minus an outer diameter of the substrate supporting apparatus)/2. 
     According to a further example of the method, the first predetermined distance may be less than or equal to (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus). 
     According to another example of the method, the second predetermined distance may be (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus)/2. 
     According to a further example of the method, after the first to eighth operations are performed, a radial length of the gap may be constant over the entire section of the gap. 
     According to another example of the method, one surface of the ring may come in contact with the substrate supporting apparatus by movement of the substrate supporting apparatus during at least one of the first to eighth operations, and the ring may be configured to move in a moving direction of the substrate supporting apparatus while maintaining the contact with the substrate supporting apparatus. 
     According to one or more embodiments, a substrate processing method of a substrate processing apparatus including a plurality of reactors is provided, wherein each reactor includes: an upper body; a substrate supporting apparatus; and a ring surrounding the substrate supporting apparatus and disposed between the substrate supporting apparatus and the upper body, and the upper body and the substrate supporting apparatus form a reaction space, a lower region of the substrate supporting apparatus forms a lower space, a gap exists between the ring and the substrate supporting apparatus, and the reaction space and the lower space communicate with each other through the gap, wherein the substrate processing method includes centering the substrate supporting apparatus with respect to the ring. 
     According to an example of the substrate processing method, the centering of the substrate supporting apparatus with respect to the ring may further include: a first operation of moving the substrate supporting apparatus in a first direction by a first predetermined distance; a second operation of moving the substrate supporting apparatus in a second direction by a second predetermined distance; a third operation of moving the substrate supporting apparatus in the second direction by the first predetermined distance; a fourth operation of moving the substrate supporting apparatus in the first direction by the second predetermined distance; a fifth operation of moving the substrate supporting apparatus in a third direction by the first predetermined distance; a sixth operation of moving the substrate supporting apparatus in a fourth direction by the second predetermined distance; a seventh operation of moving the substrate supporting apparatus in the fourth direction by the first predetermined distance; and an eighth operation of moving the substrate supporting apparatus in the third direction by the second predetermined distance, wherein the second direction may be opposite to the first direction, and the fourth direction may be perpendicular to the first direction and the second direction and may be opposite to the third direction. 
     According to a further example of the substrate processing method, the ring may be seated on the upper body to be slidable to the upper body. 
     According to a further example of the substrate processing method, the ring may be installed to be movable by a pushing force of the substrate supporting apparatus. 
     According to a further example of the substrate processing method, each reactor may include: an alignment device for moving the substrate supporting apparatus; and a controller connected to the alignment device and for controlling movement of the substrate supporting apparatus, wherein the substrate processing method may further include: before the first operation, inputting an inner diameter of the ring and an outer diameter of the substrate supporting apparatus to the controller. 
     According to a further example of the substrate processing apparatus, the controller may be configured to calculate the first predetermined distance and the second predetermined distance using the inner diameter of the ring and the outer diameter of the substrate supporting apparatus that are input. 
     According to an example of the substrate processing apparatus, the substrate processing apparatus may process a batch of substrates at a time, and may include: a series or a plurality of series of processing for a batch of substrates; centering the substrate supporting apparatus with respect to the ring; performing a series or a plurality of series of processing for another batch of substrates; and repeatedly centering the substrate supporting apparatus with respect to the ring. 
     According to a further example of the substrate processing apparatus, the centering of the substrate supporting apparatus with respect to the ring may be performed simultaneously or at different times for each reactor. 
     According to a further example of the substrate processing apparatus, the centering of the substrate supporting apparatus with respect to the ring may be performed during an idle period of each reactor. 
     According to another example of the substrate processing apparatus, each reactor may further include: a first gas inlet introducing gas into the reaction space; and a second gas inlet introducing gas into the lower space, wherein the ring may control a pressure balance between the reaction space and the lower space by adjusting a gap between the ring and the substrate supporting apparatus. 
     According to a further example of the substrate processing apparatus, the second gas inlet may adjust the amount of gas introduced into the lower space to prevent the gas in the reaction space from being introduced into the lower space through the gap. 
     According to a further example of the substrate processing apparatus, by centering the substrate supporting apparatus with respect to the ring, a radial length of the gap is constant over the entire section of the gap, thereby effectively preventing the gas in the reaction space from being introduced into the lower space. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a cross-sectional view of a chamber including a plurality of reactors; 
         FIG.  2    is a top view of a chamber including a plurality of reactors; 
         FIG.  3    is a view of a substrate processing apparatus according to embodiments; 
         FIG.  4    is a view of a flow of process gas and filling gas in a gap between a substrate supporting apparatus and a ring; 
         FIG.  5    is a view of a substrate supporting apparatus eccentric with respect to a ring as viewed from the top of the substrate supporting apparatus; 
         FIG.  6 A  is a view of temperature distribution of a substrate supporting apparatus when the substrate supporting apparatus is centered with respect to a ring, and  FIG.  6 B  is a view of temperature distribution of the substrate supporting apparatus when the substrate supporting apparatus is eccentric to the left with respect to the ring; 
         FIG.  7    is a view of a substrate processing apparatus according to embodiments; 
         FIG.  8    is a view of a substrate processing apparatus according to other embodiments; 
         FIG.  9    is a view of a substrate processing method according to embodiments; 
         FIGS.  10  and  11    are partial enlarged views of a substrate processing apparatus according to embodiments; 
         FIG.  12    is a view of an example of a substrate supporting apparatus having a misaligned centering position; 
         FIGS.  13 A to  13 D  are views of a process of centering the substrate supporting apparatus of  FIG.  12    with respect to a ring using a substrate processing method according to embodiments; 
         FIG.  14    is a view of a substrate supporting apparatus centered with respect to a ring by a substrate processing method according to embodiments as viewed from the top of the substrate supporting apparatus; 
         FIG.  15    is a view of another example of a substrate supporting apparatus having a misaligned centering position; 
         FIGS.  16 A to  16 D  are views of a process of centering the substrate supporting apparatus of  FIG.  15    with respect to a ring using a substrate processing method according to embodiments; 
         FIGS.  17  and  18    are views of a substrate processing method according to embodiments; 
         FIG.  19    is a view of a substrate processing apparatus according to embodiments including two or more reactors; 
         FIG.  20    is a view of an alignment device of a substrate processing apparatus according to embodiments; 
         FIG.  21    is a view of an alignment device support module of a substrate processing apparatus according to embodiments; 
         FIG.  22    is a view of a substrate processing apparatus according to other embodiments; 
         FIG.  23    is a view of a substrate processing apparatus according to other embodiments; and 
         FIG.  24    is a view of a substrate processing apparatus according to other embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the disclosure. As used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes”, “comprises” and/or “including”, “comprising” used herein specify the presence of stated features, integers, steps, processes, members, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, processes, members, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     It will be understood that, although the terms first, second, etc. may be used herein to describe various members, components, regions, layers, and/or sections, these members, components, regions, layers, and/or sections should not be limited by these terms. These terms do not denote any order, quantity, or importance, but rather are only used to distinguish one component, region, layer, and/or section from another component, region, layer, and/or section. Thus, a first member, component, region, layer, or section discussed below could be termed a second member, component, region, layer, or section without departing from the teachings of embodiments. 
     Embodiments of the disclosure will be described hereinafter with reference to the drawings in which embodiments of the disclosure are schematically illustrated. In the drawings, variations from the illustrated shapes may be expected as a result of, for example, manufacturing techniques and/or tolerances. Thus, the embodiments of the disclosure should not be construed as being limited to the particular shapes of regions illustrated herein but may include deviations in shapes that result, for example, from manufacturing processes. 
       FIG.  3    is a schematic cross-sectional view of one reactor of a substrate processing apparatus according to embodiments. 
     One reactor in the substrate processing apparatus may include an upper body and a lower body. The upper body and the lower body may be connected to each other. In more detail, the upper body and the lower body of the reactor may form an inner space while face-contacting and face-sealing each other. The reactor may include a substrate supporting apparatus in the inner space thereof and a ring surrounding the substrate supporting apparatus and disposed between the substrate supporting apparatus and the upper body. 
     Each reactor may be a reactor in which an atomic layer deposition (ALD) or a chemical vapor deposition (CVD) process is performed. 
     An upper body  16  of the reactor may include a first gas inlet  1 , a gas supply  2 , exhausters  6  and  7 , and a ring  8 . A lower body  13  of the reactor may include a second gas inlet  9 . The upper body  16  and the substrate supporting apparatus  3  may form a reaction space  5 . The lower body  13  and the substrate supporting apparatus  3  may form a lower space  10 . 
     The ring  8  surrounds the substrate supporting apparatus  3  and may be disposed between the substrate supporting apparatus  3  and the upper body  16 . The ring  8  may generally have a circular ring shape, but is not limited thereto. For example, when the substrate supporting apparatus  3  is rectangular, the ring  8  may have a rectangular ring shape. The ring  8  may be fixed to the upper body  16 . 
     A gap G may be between the ring  8  and the substrate supporting apparatus  3 . The reaction space  5  and the lower space  10  may communicate with each other through the gap G. 
     The substrate supporting apparatus  3  may include a susceptor body for supporting a substrate and a heater for heating the substrate supported by the susceptor body. For loading/unloading of the substrate, the substrate supporting apparatus  3  may be configured to be connected to a drive motor  11  provided to one side of the substrate supporting apparatus and to be vertically movable. The lower body  13  of the reactor may be configured to be vertically movable by a drive motor  19  connected thereto through a lower body support  18  of the reactor. 
     However, as shown in  FIG.  8   , when the lower body  13  of the reactor, the lower body support  18  of the reactor, and a chamber lower wall  20  are integral, for loading/unloading of the substrate, the reactor may include a substrate insertion portion  700  in the lower body  13  of the reactor instead of the drive motor  19 . 
     According to another embodiment, as shown in  FIG.  23   , the upper body  16  and the lower body  13  of the reactor of  FIG.  3    may be integral. In this case, the second gas inlet  9  may be configured on one side of the chamber lower wall  20 . According to such a variation, only the upper body  16  of the reactor, the substrate supporting apparatus  3 , and the ring  8  may center the substrate supporting apparatus  3 . 
     According to a further alternative embodiment, as shown in  FIG.  24   , without the lower body  13  of the reactor, the lower body support  18 , and the drive motor  19  of  FIG.  3   , the upper body  16  of the reactor and the substrate supporting apparatus  3  alone may form a deposition apparatus and a reaction space. In this case, reactors in the chamber may share the lower space  10 . In addition, the second gas inlet  9  may be configured on one side of the chamber lower wall  20 . 
     A stretchable portion  12  may be between a lower surface of the lower body  13  and the drive motor  11 . In more detail, the stretchable portion  12  may include a first stretchable portion  12   a  connecting the lower surface of the lower body  13  to the chamber lower wall  20  and a second stretchable portion  12   b  connecting the chamber lower wall  20  to the drive motor  11 . The stretchable portion  12  may be between the lower surface of the lower body  13  and the drive motor  11  to isolate the lower space  10  from the outside. 
     The second stretchable portion  12   b  may be stretched according to movement of the substrate supporting apparatus  3 . For example, the second stretchable portion  12   b  may have a corrugated configuration (e.g., a bellows). In this case, when the substrate supporting apparatus  3  and the drive motor  11  are raised, the second stretchable portion  12   b  may contract, and when the substrate supporting apparatus  3  and the drive motor  11  are lowered, the second stretchable portion  12   b  may expand. 
     In an alternative embodiment, the second stretchable portion  12   b  may have elasticity. For example, the elasticity of the second stretchable portion  12   b  may be adjusted so as to be stretched or contracted in response to vertical movement of the substrate supporting apparatus  3  so that shielding between the lower surface of the lower body  13  and the drive motor  11  may be maintained. 
     Process gas introduced through the first gas inlet  1  may be supplied to the reaction space  5  and the substrate through the gas supply  2 . The gas supply  2  may be a shower head, and a base of the shower head may include a plurality of gas supply holes formed to eject the process gas (e.g., in the vertical direction). The process gas supplied on the substrate may undergo a chemical reaction with the substrate or a chemical reaction between gases, and then deposit a thin film or etch a thin film on the substrate. 
     In a plasma process, high frequency (RF) power supplier may be electrically connected to the gas supply  2  functioning as one electrode. In more detail, an RF rod  4  connected to the RF power supplier may be connected to the gas supply  2 . In this case, upper RF power is supplied to the gas supply  2  through an RF power supplier consisting of a RF generator and a RF matcher, and the RF rod  4 , and reaction gas introduced into the reaction space  5  through the first gas inlet  1  may be activated to generate plasma. 
     In the reaction space  5 , residual gas or un-reacted gas remaining after the chemical reaction with the substrate may be exhausted to the outside through an exhaust space  7  and an exhaust pump (not shown) in an exhauster  6 . An exhaust method may be upper exhaust or lower exhaust. 
       FIG.  4    is a view of a flow of process gas and filling gas in a gap between a substrate supporting apparatus and a ring. 
     Referring to  FIG.  4   , process gas introduced through the first gas inlet  1  may be supplied to the reaction space  5  and the substrate through the gas supply  2 . 
     In addition, the filling gas may be introduced into the lower space  10  through the second gas inlet  9 . This filling gas forms a gas curtain in the gap G between the substrate supporting apparatus  3  and the ring  8  to prevent the gas in the reaction space  5  from flowing into the lower space  10 . For example, the filling gas may be nitrogen or argon. Alternatively, gas having a lower discharge rate than the gas supplied to the reaction space  5  may be supplied to the lower space  10  through the second gas inlet  9  in order to prevent parasitic plasma from being generated in the lower space  10  when the plasma is generated in the reaction space  5 . 
     As shown in  FIG.  4   , the ring  8  may be between the upper body  16  and the substrate supporting apparatus  3 . For example, the ring  8  may include a gas flow control ring (FCR). The ring  8  may control pressure balance between the reaction space  5  and the lower space  10  by adjusting the width of a gap between the upper body  16  and the substrate supporting apparatus  3 . 
     In more detail, the ring  8  adjusts the width of the gap between the upper body  16  and the substrate supporting apparatus  3 , that is, a width of the gap between the ring  8  and the substrate supporting apparatus  3 . Thus, the ring  8  may control widths of the flow of the filling gas and the process gas around the gap, thereby controlling the pressure of the filling gas and process gas. As shown in  FIG.  4   , widths A and B of the gap G between the substrate supporting apparatus  3  and the ring  8  remain the same (i.e., A=B), thereby balancing the pressure between the reaction space  5  and the lower space  10  over the entire section of the gap G. 
     However, as described above, in a high temperature process, a mismatch of each portion of the reactor occurs due to a difference in thermal expansion due to the temperature difference between parts of the chamber and the reactor. For example, due to a difference in thermal expansion between a chamber upper wall  17 , the upper portion  16  and the lower body  13  of the reactor, and the chamber lower wall  20 , a mismatch between components of the reactor occurs, which may cause a centering position of the substrate supporting apparatus  3  with respect to the ring  8  to be misaligned. That is, the widths A and B of the gap G may not be constant over the entire section (A≠B). Some examples in which the substrate supporting apparatus  3  is eccentric with respect to the ring  8  are shown in  FIG.  5   . 
     As such, when the gap between the substrate supporting apparatus  3  and the ring  8  is not constant (A≠B), the pressure balance of the filling gas and reaction gas in the gap G surrounding the edge of the substrate supporting apparatus  3  may vary depending on the position of the gap G. 
     In addition, in a high temperature process, since the temperature difference between the substrate supporting apparatus  3  and the ring  8  is greater (e.g., the temperature of the substrate supporting apparatus  3  is about 500° C. and the temperature of the ring  8  is about 200° C.), temperature distribution of the substrate supporting apparatus  3  may vary depending on alignment of the substrate supporting apparatus  3  with the ring  8 . This is because the closer the ring  8  is to the substrate supporting apparatus  3 , the greater the influence on thermal conductivity of the substrate supporting apparatus  3 . From simulation results shown in  FIG.  6 A , it can be seen that the temperature distribution of a substrate supporting apparatus is constant when the substrate supporting apparatus is centered with respect to a ring. Also, from simulation results shown in  FIG.  6 B , it can be seen that the temperature distribution of a substrate supporting apparatus is not constant when the substrate supporting apparatus is eccentric to the left with respect to a ring. 
     That is, when the gap between the substrate supporting apparatus  3  and the ring  8  is not constant (A≠B), not only does the pressure balance of the filling gas and the reaction gas depend on the position of the gap G, but the temperature distribution of the substrate supporting apparatus  3  may not be constant. This may lead to non-uniformity of a thin film on a substrate, in particular thin film non-uniformity at the edge of the substrate, which may increase a defect rate of a semiconductor device. 
     Therefore, there is a need for a method capable of correcting the shift of the center of a substrate supporting apparatus with the high temperature use of a substrate processing apparatus and keeping the widths A and B of the gap G between the substrate supporting apparatus  3  and the ring  8  constant. 
       FIG.  7    is a schematic cross-sectional view of a substrate processing apparatus including a plurality of reactors, according to embodiments. 
     Unlike the reactors of  FIGS.  1  and  3   , the reactor of  FIG.  7    may further include an alignment device  14  and a controller  15  between the substrate supporting apparatus  3  and the drive motor  11 . 
     The alignment device  14  and the controller  15  may be supported by an assembly support  21 . 
     The alignment device  14  may be configured to move the substrate supporting apparatus  3 . For example, the alignment device  14  may align left and right positions of the substrate supporting apparatus  3  to align the substrate supporting apparatus  3  in the reactor. 
     The controller  15  is connected to the alignment device  14  and may be configured to control the movement of the substrate supporting apparatus  3  by controlling the alignment device  14 . Although  FIG.  7    shows that each reactor has the controller  15  individually, in other embodiments, each reactor may share one controller. That is, one controller may control the movement of substrate supporting apparatuses of all reactors. 
     An alignment method of the substrate supporting apparatus  3  by the alignment device  14  and the controller  15  will be described in detail later below with reference to  FIGS.  9  to  18   . 
     Also, unlike in the substrate processing apparatus of  FIGS.  1  and  4   , the ring  8  disposed between the upper body  16  and the substrate supporting apparatus  3  may be seated on the upper body  16  to be slidable or floatable with respect to the upper body  16 . For example, when a pushing force is applied to the ring  8 , the ring  8  may be moved in the direction of force exerted on the upper body  16  by the pushing force. 
     In more detail, the upper body  16  may include a step S toward the reaction space inside a lower portion of the upper body  16 . In this case, the ring  8  may be seated inside the step S. When the ring  8  is seated on the step S of the upper body  16 , a wall of the step S and an outer wall of the ring  8  may be apart by a certain interval. In a further embodiment, the step S may further include a pad P, and the ring  8  may be seated on the pad P to be slidable with respect to the pad P. The ring  8  may be installed to be movable in the step S by the pushing force of the substrate supporting apparatus  3 . For example, as will be described later below, the ring  8  may have one surface which comes in contact with the substrate supporting apparatus  3  by movement of the substrate supporting apparatus  3  and may be moved in the direction of the movement of the substrate supporting apparatus  3  while maintaining the contact with the substrate supporting apparatus  3 . 
     In another embodiment, the ring  8  may be fixed with respect to the upper body  16 . 
       FIG.  8    is a view of a substrate processing apparatus according to other embodiments. 
     Unlike the substrate process of  FIG.  7   , the lower body  13  of the reactor, the lower body support  18  of the reactor, and the chamber lower wall  20  may be integral. In this case, the lower body  13  of the reactor may not vertically move for loading/unloading of a substrate. Thus, the reactor may include a substrate insertion portion  700  in the lower body  13  of the reactor instead of the drive motor  19  of  FIG.  7   . 
     For loading/unloading of the substrate, the substrate supporting apparatus  3  may be connected to a drive motor  11  provided to one side of the substrate supporting apparatus  3  to vertically move, and the substrate may be inserted through the substrate insertion portion  700 . 
     In a further embodiment, as shown in  FIG.  23   , an upper body and a lower body of a reactor, and a chamber lower wall may be integral. In this case, the second gas inlet  9  may be provided in the chamber lower wall  20  instead of the lower body. 
       FIG.  9    is a view of a substrate processing method according to embodiments. 
     Referring to  FIG.  9   , in operation  401 , a substrate supporting apparatus may move in a first direction by a first predetermined distance. 
     The first direction may be a direction horizontal to the ground. In an alternative embodiment, the first direction may be a −x-axis direction. For example, the substrate supporting apparatus may be moved in the −x-axis direction towards the ring. 
     The first predetermined distance may be greater than or equal to (an inner diameter of the ring minus an outer diameter of the substrate supporting apparatus)/2. The first predetermined distance may be less than or equal to (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus). 
     While the substrate supporting apparatus is moved in operation  401 , the substrate supporting apparatus may or may not come in contact with the ring. In the former case, when the substrate supporting apparatus continues to move even after the substrate supporting apparatus comes in contact with the ring, the ring may be moved in the first direction by a pushing force of the substrate supporting apparatus. In this regard, it will be described later below with reference to  FIG.  13 A . In the latter case, since the substrate supporting apparatus is not in contact with the ring, no pushing force acts on the ring and thus the ring may not move. In this regard, it will be described later below with reference to  FIG.  16 A . 
     Then, in operation  402 , the substrate supporting apparatus may move in a second direction by a second predetermined distance. 
     The second direction may be opposite to the first direction. For example, when the first direction is the −x-axis direction, the second direction may be an x-axis direction. 
     The second predetermined distance may be (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus)/2. As will be described later below, the second predetermined distance has this value such that the substrate supporting apparatus may be centered with respect to the ring. 
     Then, in operation  403 , the substrate supporting apparatus may move in the second direction by the first predetermined distance. 
     While the substrate supporting apparatus is moved in operation  403 , the substrate supporting apparatus may come in contact with the ring. When the substrate supporting apparatus continues to move even after the substrate supporting apparatus comes in contact with the ring, the ring may be moved in the second direction by the pushing force of the substrate supporting apparatus. In this regard, it will be described later below with reference to  FIGS.  13 C and  16 C . 
     Thereafter, in operation  404 , the substrate supporting apparatus may move in the first direction by the second predetermined distance. 
     When the second direction is opposite to the first direction, it should be noted that after operations  401  to  404  are performed, a final position of the substrate supporting apparatus is the same as an initial position of the substrate supporting apparatus. Because, during operations  401  to  404 , the substrate supporting apparatus is moved by the first predetermined distance in the first direction and a—first direction, respectively, and also by the second predetermined distance in the first direction and the—first direction respectively. Nevertheless, through operations  401  to  404 , the substrate supporting apparatus may be centered with respect to the ring in the first direction. This is because the position of the ring is changed by the substrate supporting apparatus during operation  401  and/or operation  403 . That is, the disclosure centers the substrate supporting apparatus with respect to the ring by correcting the position of the ring instead of correcting the position of the substrate supporting apparatus. In this regard, it will be described later below with reference to  FIGS.  12  to  13 D . 
     Then, in operation  405 , the substrate supporting apparatus may be moved in a third direction by the first predetermined distance. 
     The third direction may be a direction horizontal to the ground. In addition, the third direction may be perpendicular to the first direction and the second direction. In an alternative embodiment, the third direction may be a y-axis direction. For example, the substrate supporting apparatus may be moved in the y-axis direction towards the ring. 
     While the substrate supporting apparatus is moved in operation  405 , the substrate supporting apparatus may or may not come in contact with the ring. In the former case, when the substrate supporting apparatus continues to move even after the substrate supporting apparatus comes in contact with the ring, the ring may be moved in the third direction by the pushing force of the substrate supporting apparatus. 
     Thereafter, in operation  406 , the substrate supporting apparatus may move in a fourth direction by the second predetermined distance. 
     In addition, the fourth direction may be perpendicular to the first direction and the second direction. Furthermore, the fourth direction may be opposite to the third direction. For example, when the third direction is the y-axis direction, the fourth direction may be the −y-axis direction. 
     Thereafter, in operation  407 , the substrate supporting apparatus may be moved in the fourth direction by the first predetermined distance, and in operation  408 , the substrate supporting apparatus may be moved in the third direction by the second predetermined distance. 
     While the substrate supporting apparatus is moved in operation  407 , the substrate supporting apparatus may or may not come in contact with the ring. In the former case, when the substrate supporting apparatus continues to move even after the substrate supporting apparatus comes in contact with the ring, the ring may be moved in the fourth direction by a pushing force of the substrate supporting apparatus. 
     In the same context as operations  401  to  404 , when the fourth direction is opposite to the third direction, after operations  405  to  408  are performed, the final position of the substrate supporting apparatus is the initial position of the substrate supporting apparatus. Nevertheless, through operations  401  to  404 , the substrate supporting apparatus may be centered with respect to the ring in the first direction. This is because the ring is moved in the third direction or the fourth direction by the substrate supporting apparatus during operation  401  and/or operation  403 . 
       FIG.  10    is a partial enlarged view of a substrate-processing device according to embodiments. Only one of a plurality of reactors of the substrate processing apparatus is shown for ease of understanding, and the configuration of an upper body of the reactor is omitted. 
       FIG.  10    shows the substrate supporting apparatus  3  centered with respect to the ring  8 . 
     As shown in  FIG.  10   , the length of an inner diameter of the ring  8  is D, and the length of an outer diameter of the substrate supporting apparatus  3  is C. The length D of the inner diameter of the ring  8  and the length C of the outer diameter of the substrate supporting apparatus  3  are constant. The length D of the inner diameter of the ring  8  and the length C of the outer diameter of the substrate supporting apparatus  3  may be input to the controller  15  before operation  401  of  FIG.  9   . The controller  15  may calculate a moving distance of the substrate supporting apparatus  3  using the input length D of the inner diameter of the ring  8  and the input length C of the outer diameter of the substrate supporting apparatus  3 . As described above, according to the disclosure, centering of the substrate supporting apparatus may be performed only by the length D of the inner diameter and the length C of the outer diameter of the ring  8  without having to install a separate diagnostic mechanism for measuring a distance between the substrate supporting apparatus  3  and the ring  8 . This will be described later below. 
     The widths of the gaps G between the substrate supporting apparatus  3  and the ring  8  are A and B on the left and right sides of  FIG.  10   , respectively. 
     Thus, a relational expression of D=A+B+C is established (where A and B are variables and C and D are constants). 
     In this example, since the substrate supporting apparatus  3  is centered with respect to the ring  8 , the widths A and B of the gaps G between the substrate supporting apparatus  3  and the ring  8  are the same. That is, A=B=(D−C)/2. The initial values of A and B may also be input to the controller  15 . 
     As described with reference to  FIGS.  9  and  13 A to  13 D , the method according to the disclosure may use the following principle. The disclosure may use the alignment device  14  to contact the substrate supporting apparatus  3  to one side of the ring  8  to center the substrate supporting apparatus  3 . For example, the substrate supporting apparatus  3  may move to the left to contact one side of the ring  8 . As a result, A=0. In order to bring the substrate supporting apparatus  3  into contact with one side of the ring  8 , the first predetermined distance in the method of  FIG.  9    may be greater than or equal to (D−C)/2. Then, a value of B, B=(D−C) (D and C are constants, where A=0), may be derived from a relational expression D=A+B+C. Again using the alignment device  14 , the substrate supporting apparatus  3  may be moved in the opposite direction by B/2=(D−C)/2. Therefore, A′=B′=(D−C)/2 (that is, A=A′ and B=B′), and thus, the centering of the substrate supporting apparatus  3  may be completed. In an embodiment, a calculation relating to a moving distance of the substrate supporting apparatus  3  may be performed by the controller  15 . As described above, the controller  15  may calculate a moving distance of the substrate supporting apparatus  3  using only the input length D of the inner diameter of the ring  8  and the input length C of the outer diameter of the substrate supporting apparatus  3 . 
     According to a further embodiment of the disclosure, as shown in  FIGS.  10  and  11   , the upper body  16  may include the step S toward the reaction space inside a lower portion thereof. In this case, the ring  8  may be seated inside the step S. In a further embodiment, the step S may further include the pad P, and the ring  8  may be seated on the pad P. The ring  8  may be seated on the pad P to be slidable with respect to the pad P. In the present embodiment, a length of the pad P is g. 
     A radial thickness of the ring  8  is f. Preferably, the length g of the pad P is longer than or equal to the radial thickness f of the ring  8  such that the ring  8  is seated completely on the pad P when the ring  8  is moved. 
     Preferably, an inner diameter I of the upper body is less than the sum of an inner diameter D of the ring  8  and the radial thickness f of the ring  8 . Due to this configuration, even if the ring  8  is pushed to one side to the maximum as shown in  FIG.  11   , the ring  8  may still be seated on the pad P on the opposite side. 
     The distance from the outer wall of the ring  8  to the step S is e, and may vary as the ring  8  is moved. 
     As described above, in the method according to the disclosure, the first predetermined distance may be greater than or equal to (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus)/2. When the radial thickness f of the ring is less than the length g of the pad P, the substrate supporting apparatus may collide with a wall of the lower body during the movement of the first predetermined distance. Therefore, it is preferable that the radial thickness f of the ring is greater than (the inner diameter D of the ring minus an outer diameter C of the substrate supporting apparatus)/2 which is the moving distance of the substrate supporting apparatus. Alternatively, in a variation, as shown in  FIG.  22   , a thickness h 1  of the ring  8  may be the same as a thickness h 2  of the substrate supporting apparatus  3  such that the substrate supporting apparatus does not collide with the wall of the lower body  13  during the movement of the first predetermined distance. That is, compared with  FIG.  10   , such a technical effect may be achieved by configuring an upper surface of the pad P not to be higher than a lower surface of the substrate supporting apparatus  3 . In this way, the ring  8  may be movable on the pad P and the substrate supporting apparatus  3  does not hit the wall of the lower body  13  while moving by the first predetermined distance. 
     According to further embodiments, as shown in  FIG.  11   , the ring  8  may further include a stopper ST at a lower portion thereof. The stopper ST may prevent the ring  8  from moving excessively into the pad P of the upper body. The stopper ST may be between an inner wall of the ring  8  and a lower surface of the ring  8 . 
     As described above, the center of the substrate supporting apparatus may move according to thermal expansion of the substrate processing apparatus.  FIG.  12    is a view of an example of a substrate supporting apparatus having a misaligned centering position. 
     Widths of the gaps G between the substrate supporting apparatus  3  and the ring  8  are A 1  and B 1  on the left and right sides of  FIG.  12   , respectively (where A 1  and B 1  are non-zero constants and A 1 ≠B 1 ). 
     Thus, a relational expression of D=A 1 +B 1 +C is established. 
     In this example, the substrate supporting apparatus  3  is not centered with respect to the ring  8 , and the substrate supporting apparatus  3  is biased to the left of  FIG.  12    (i.e., A 1 &lt;B 1 ). 
       FIGS.  13 A to  13 D  show a process of centering the substrate supporting apparatus  3  of  FIG.  12    with respect to the ring  8  using the substrate processing method of  FIG.  9   . 
     For convenience of explanation, hereinafter, a first direction is a −x-axis direction (left side in the drawing), a second direction is an x-axis direction (right side in the drawing), a first predetermined distance is m (m&gt;(D−C)/2), and a second predetermined distance is (the inner diameter D of the ring minus the outer diameter C of the substrate supporting apparatus)/2. 
     First, referring to  FIGS.  9  and  13 A , according to operation  401  of  FIG.  9   , the substrate supporting apparatus  3  is moved by a first predetermined distance m in the first direction (left direction) by the controller  15  and the alignment device  14 . 
     In this example, since m&gt;A 1 , during operation  401 , the substrate supporting apparatus  3  comes in contact with the ring  8  after moving by A 1  and may further move the remaining distance (m−A 1 ) while maintaining contact with the ring  8 . Therefore, the ring  8  may move by (m−A 1 ) in the moving direction (i.e., the left direction) of the substrate supporting apparatus  3  while maintaining the contact with the substrate supporting apparatus  3 . 
     Accordingly, on the left side, a distance from the outer wall of the ring  8  to the step S is e−(m−A 1 ). Correspondingly, on the right side, the distance from the outer wall of the ring  8  to the step S is e+(m−A 1 ). 
     Also, on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  is 0, and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is (D−C). 
     Next, referring to  FIGS.  9  and  13 B , according to operation  402  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the second predetermined distance ((D−C)/2) in the second direction (right direction). 
     In operation  402  of  FIG.  9   , the position of the ring  8  does not change because the substrate supporting apparatus  3  does not push the ring  8  while moving. Thus, even after operation  402  is performed, on the left side, the distance from the outer wall of the ring  8  to the step S is still e−(m−A 1 ). 
     Further, due to the movement of the substrate supporting apparatus  3 , on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  is (D−C)/2, and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is also (D−C)/2. That is, by operations  401  and  402 , the substrate supporting apparatus  3  is centered with respect to the ring  8  on the x-axis. 
     However, as described with reference to  FIGS.  15  and  16 A to  16 D , when the first predetermined distance m is less than a distance A 2  between the substrate supporting apparatus  3  and the ring  8  in the −x direction but greater than a distance B 2  between the substrate supporting apparatus  3  and the ring  8  in the +x direction (i.e., B 2 &lt;m&lt;A 2 ), in operations  401  and  402  alone, the substrate supporting apparatus  3  may not be centered with respect to the ring  8 . That is, a centering calculation by the basic equation in the −x direction is impossible and a centering process in the +x direction is additionally required. 
     Operations  403  and  404  described later below are performed to center the substrate supporting apparatus  3  in all situations, including these situations. 
     Referring to  FIGS.  9  and  13     c , according to operation  403  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the first predetermined distance m in the second direction (right direction). 
     In this example, since it is assumed that the first predetermined distance m is greater than (D−C)/2, during operation  403 , the substrate supporting apparatus  3  is brought into contact with the ring  8  after moving by (D−C)/2 and may further move the remaining distance (D−C)/2 while maintaining the contact with the ring  8 . Therefore, the ring  8  may further move by (m−(D−C)/2) in the moving direction (i.e., the right direction) of the substrate supporting apparatus  3  while maintaining the contact with the substrate supporting apparatus  3 . 
     Accordingly, on the right side, a distance from the outer wall of the ring  8  to the step S is e−A 1 +(D−C)/2. Accordingly, on the left side, a distance from the outer wall of the ring  8  to the step S is e+A 1 −(D−C)/2. 
     Also, on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  may be 0, and on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  may be (D−C). 
     Next, referring to  FIGS.  9  and  13 D , according to operation  404  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the second predetermined distance ((D−C)/2) in the first direction (left direction). 
     In operation  404  of  FIG.  9   , the position of the ring  8  does not change because the substrate supporting apparatus  3  does not push the ring  8  while moving. Thus, even after operation  404  is performed, on the right side, the distance from the outer wall of the ring  8  to the step S is still e−A 1 +(D−C)/2. 
     Further, due to the movement of the substrate supporting apparatus  3 , on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  is (D−C)/2, and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is also (D−C)/2. That is, by operations  403  and  404 , the substrate supporting apparatus  3  is centered with respect to the ring  8  on the x-axis. 
     As described above, after operations  401  to  404  are performed, the final position (i.e., position in  FIG.  13 D ) of the substrate supporting apparatus  3  is the same as the initial position (i.e., position in  FIG.  12   ) of the substrate supporting apparatus  3 . Nevertheless, comparing  FIGS.  12  and  13 D , it can be seen that the substrate supporting apparatus  3 , which is biased to the left with respect to the ring  8 , is centered by operations  401  to  404  of  FIG.  9   . This is because the position of the ring  8  is changed by the substrate supporting apparatus  3  during operations  401  and  403 . Indeed, it can be seen that the ring  8  of  FIG.  13 D  moves to the left by (D−C)/2−A 1  compared to the ring  8  of  FIG.  12   . In a similar logic, when the above method is performed on a substrate supporting apparatus that is biased to the right with respect to the ring, the substrate supporting apparatus may be centered with respect to the ring by moving the ring rather than the substrate supporting apparatus to the right. 
     That is, the disclosure centers the substrate supporting apparatus  3  with respect to the ring  8  by correcting the position of the ring  8  instead of correcting the position of the substrate supporting apparatus  3 . 
       FIGS.  13 A to  13 D  show a process of centering the substrate supporting apparatus  3  with respect to the ring  8  on the x-axis by performing operations  401  to  404  of  FIG.  9   . In a similar manner, when performing operations  405  to  408  of  FIG.  9    with respect to the y-axis, the substrate supporting apparatus  3  may also be centered with respect to the ring  8  on the y-axis. 
       FIG.  14    is a view of a substrate supporting apparatus centered with respect to a ring by the substrate processing method of  FIG.  9    as viewed from the top of a reactor. 
     In the present embodiment, the first direction is the −x-axis direction (left side in the drawing), the second direction is the x-axis direction (right side in the drawing), the third direction is the y-axis direction (upward in the drawing), the fourth direction is the −y-axis direction (downward in the drawing), and the second predetermined distance is (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus)/2. 
     (a) to (e) of  FIG.  14    show a process of centering the substrate supporting apparatus with respect to the ring on the x-axis by performing operations  401  to  404  of  FIG.  9   . Next, as shown in (f) to (i) of  FIG.  14   , by performing operations  405  to  408  of  FIG.  9    with respect to the y-axis, the substrate supporting apparatus may be centered with respect to the ring on the y-axis as well. In this way, the substrate supporting apparatus may be centered with respect to the ring  8  as a whole. 
     In more detail,  FIG.  14  ( a )  shows a state in which the substrate supporting apparatus is eccentric about 0.5 mm from the center of the inner diameter of the ring to the left. Then, according to operation  401  of  FIG.  9   , an alignment device moves the substrate supporting apparatus to the left to come in contact with one surface of the ring (see  FIG.  14  ( b ) ). Here, as described above, the controller  15  (of  FIG.  10   ) may calculate a moving distance of the substrate supporting apparatus using the input inner diameter of the ring and the input outer diameter of the substrate supporting apparatus. That is, the controller may calculate the first predetermined distance and the second predetermined distance using the input inner diameter of the ring and the input outer diameter of the substrate supporting apparatus. 
     Then, according to operation  402  of  FIG.  9   , the alignment device moves the substrate supporting apparatus to the right by the calculated second predetermined distance (see  FIG.  14  ( c ) ). Here, as described above, since the second predetermined distance is (the inner diameter of the ring minus the outer diameter of the substrate supporting apparatus)/2, the substrate supporting apparatus may be centered with respect to the ring on the x-axis. 
     Next, according to operation  403  of  FIG.  9   , the alignment device moves the substrate supporting apparatus to the right by the first predetermined distance to contact one surface of the ring (see  FIG.  14  ( d ) ). According to operation  404  of  FIG.  9   , the alignment device moves the substrate supporting apparatus to the left by the calculated second predetermined distance (see  FIG.  14  ( e ) ). The substrate supporting apparatus may be centered with respect to the ring on the x-axis. 
     The alignment device may now center the substrate supporting apparatus on the y-axis. First, according to operation  405  of  FIG.  9   , the alignment device moves the substrate supporting apparatus by a first predetermined distance in a third direction, that is, in the y-axis direction. In a preferred embodiment, the first predetermined distance is (the inner diameter of the ring—the outer diameter of the substrate supporting apparatus)/2 or more, so that the substrate supporting apparatus may come in contact with one side of the ring (see  FIG.  14 ( f ) ). Next, according to operation  405  of  FIG.  9   , the alignment device moves the substrate supporting apparatus by the second predetermined distance in a fourth direction, that is, in a −y-axis direction (see  FIG.  14 ( g ) ). The substrate supporting apparatus may be centered with respect to the ring on the y-axis. According to operation  407  of  FIG.  9   , the alignment device moves the substrate supporting apparatus by the first predetermined distance in the fourth direction, that is, in the −y-axis direction (see  FIG.  14 ( h ) ). The substrate supporting apparatus may come in contact with one side of the ring. Finally, according to operation  408  of  FIG.  9   , the alignment device moves the substrate supporting apparatus by the second predetermined distance in the third direction, that is, in the y-axis direction (see  FIG.  14 ( i ) ). The substrate supporting apparatus may be centered with respect to the ring on the y-axis. 
     As such, the centering of the substrate supporting apparatus may include x-axis centering and y-axis centering. In four directions (x-axis direction, −x-axis direction, y-axis direction, −y-axis direction), the substrate supporting apparatus is centered such that the gap between the substrate supporting apparatus and the ring is constant. As such, a radial length of the gap between the substrate support and the ring may be constant over the entire section of the gap. The constant radial length of this gap may maintain a uniform pressure between gas in the reaction space  5  (of  FIG.  7   ) and filling gas flowing into the lower space  10  (of  FIG.  7   ) over the entire section of the gap, and may prevent the gas in the reaction space from entering the lower space  10 . 
       FIG.  15    is a view of another example of a substrate supporting apparatus having a misaligned centering position.  FIG.  15    shows a method of centering the substrate supporting apparatus  3  when the substrate supporting apparatus  3  is eccentric to the right, unlike  FIG.  12   . 
     Widths of the gaps G between the substrate supporting apparatus  3  and the ring  8  are A 2  and B 2  on the left and right sides of the drawing, respectively (where A 2  and B 2  are non-zero constants). 
     Thus, a relational expression of D=A 2 +B 2 +C is established. 
     The substrate supporting apparatus  3  is not centered with respect to the ring  8 , and the substrate supporting apparatus  3  of  FIG.  15    is biased to the right of the drawing (i.e., B 2 &lt;A 2 ). 
     In this example, the case where the first predetermined distance is greater than or equal to (the inner diameter D of the ring minus the outer diameter C of the substrate supporting apparatus)/2 but less than A 2  will be described. 
       FIGS.  16 A to  16 D  show a process of centering the substrate supporting apparatus  3  of  FIG.  15    with respect to the ring  8  using the substrate processing method of  FIG.  9   . 
     For convenience of explanation, hereinafter, the first direction is the −x-axis direction (left side in the drawing), the second direction is the x-axis direction (right side in the drawing), the first predetermined distance is m ((D−C)/2&lt;m&lt;A 2 ), and the second predetermined distance is (D−C)/2. 
     Referring to  FIGS.  9  and  16 A , according to operation  401  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the first predetermined distance m in the first direction (left direction). 
     In this example, since m&lt;A 2 , during operation  401 , the substrate supporting apparatus  3  may not come in contact with the ring  8  even if the substrate supporting apparatus  3  moves to the left by A 2 . Since the substrate supporting apparatus  3  does not push the ring  8  as the substrate supporting apparatus  3  moves, the ring  8  may not move. That is, on the left side, a distance e from the outer wall of the ring  8  to the step S does not change. 
     Also, on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  may be (A 2 −m), and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  may be (B 2 +m). 
     Next, referring to  FIGS.  9  and  16 B , according to operation  402  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the second predetermined distance ((D−C)/2) in the second direction (right direction). 
     On the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is (B 2 +m), which is greater than the second predetermined distance, so that the substrate supporting apparatus  3  and the ring  8  do not come in contact with each other even during operation  402 . Thus, the position of the ring  8  does not change. Thus, even after operation  402  is performed, on the left side, the distance from the outer wall of the ring  8  to the step S is still e. 
     Further, due to the movement of the substrate supporting apparatus  3 , on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  is A 2 −m+(D−C)/2, and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is B 2 +m−(D−C)/2. 
     That is, by operations  401  and  402 , the substrate supporting apparatus  3  of  FIG.  15    is not centered with respect to the ring  8  on the x-axis. 
     The substrate supporting apparatus  3  of  FIG.  12    may be centered with respect to the ring on the x-axis by performing only operations  401  and  402  of  FIG.  9   , but it can be seen that the substrate supporting apparatus of  FIG.  15    may not. This is because, in  FIG.  12   , the first predetermined distance m is greater than a distance A 1  between the substrate supporting apparatus  3  and the ring  8 , but in  FIG.  15   , the first predetermined distance m is less than the distance A 2  between the substrate supporting apparatus  3  and the ring  8 . 
     In the case of  FIG.  15   , there are at least four ways in which the substrate supporting apparatus  3  may be centered with respect to the ring  8 . 
     First, since B 2 &lt;(D−C)/2&lt;A 2 &lt;(D−C) (∵D=A 2 +B 2 +C and B 2 &lt;A 2 ), the first predetermined distance m is set to (D−C). Since A 2 &lt;m, by operation  401  of  FIG.  9   , the substrate supporting apparatus  3  may always come in contact with the ring  8  and may be centered by operation  402  of  FIG.  9   . 
     However, when A 2 &gt;m is set as in  FIGS.  16 A to  16 D , the substrate supporting apparatus may be centered by performing operations  403  and  404  of  FIG.  9    as follows. 
     Referring to  FIGS.  9  and  16 C , according to operation  403  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the first predetermined distance m in the second direction (right direction). 
     In this example, since it is assumed that the first predetermined distance m is greater than (D−C)/2, during operation  403 , the substrate supporting apparatus  3  is brought into contact with the ring  8  after moving by B 2 +m−(D−C)/2 and may further move the remaining distance m−(B 2 +m−(D−C)/2)=(D−C)/2−B 2  while maintaining the contact with the ring  8 . Therefore, the ring  8  may move by ((D−C)/2−B 2 ) in the moving direction (i.e., the right direction) of the substrate supporting apparatus  3  while maintaining the contact with the substrate supporting apparatus  3 . 
     Accordingly, on the right side, a distance from the outer wall of the ring  8  to the step e−((D−C)/2−B 2 ). Correspondingly, on the left side, the distance from the outer wall of the ring  8  to the step S is e+(D−C)/2−B 2 . 
     Also, on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  may be 0, and on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  may be (D−C). 
     Next, referring to  FIGS.  9  and  16 D , according to operation  404  of  FIG.  9   , the substrate supporting apparatus  3  is moved by the second predetermined distance ((D−C)/2) in the first direction (left direction). 
     In operation  404  of  FIG.  9   , the position of the ring  8  does not change because the substrate supporting apparatus  3  does not push the ring  8  while moving. Thus, even after operation  404  is performed, on the right side, the distance from the outer wall of the ring  8  to the step S is still e−(D−C)/2+B 2 . 
     Further, due to the movement of the substrate supporting apparatus  3 , on the left side, the gap between the substrate supporting apparatus  3  and the ring  8  is (D−C)/2, and on the right side, the gap between the substrate supporting apparatus  3  and the ring  8  is also (D−C)/2. 
     That is, the substrate supporting apparatus of  FIG.  15    may not be centered with respect to the ring  8  on the x-axis by operations  401  and  402  of  FIG.  9   , but may be centered by operations  403  and  404  of  FIG.  9   . 
     As described above, after operations  401  to  404  are performed, the final position (i.e., position in  FIG.  16 D ) of the substrate supporting apparatus  3  is the same as the initial position (i.e., position in  FIG.  15   ) of the substrate supporting apparatus  3 . Nevertheless, comparing  FIGS.  15  and  16 D , it can be seen that the substrate supporting apparatus  3 , which is biased to the right with respect to the ring  8 , is also centered by operations  401  to  404  of  FIG.  9   . This is because the position of the ring  8  is changed by the substrate supporting apparatus  3  during operations  401  and  403 . In fact, it can be seen that the ring  8  of  FIG.  16 D  moves to the right by (D−C)/2−B 2  compared to the ring  8  of  FIG.  15   . 
     That is, the disclosure centers the substrate supporting apparatus  3  with respect to the ring  8  by correcting the position of the ring  8  instead of correcting the position of the substrate supporting apparatus  3 . 
     As described above, due to thermal expansion differences between the components in the chamber and the reactor, a mismatch between the components in the reactors may occur. As a result, the centering position of the substrate supporting apparatus in the reactor may be misaligned. To prevent this, the substrate processing method described above (e.g., the method of  FIG.  9   ) may be performed periodically for one or more reactors during a substrate processing process. 
       FIG.  17    schematically shows an example of a substrate processing method for periodically centering a substrate supporting apparatus. 
     In the present embodiment, the substrate processing method may be performed in one reactor or in two or more reactors. In addition, when the substrate processing method of the present embodiment is performed in two or more reactors, the substrate processing method may be performed simultaneously or at different times in two or more reactors. 
     First, in operation  1201 , one series of processing or a plurality of series of processing for one or more substrates may be performed. The substrate processing may include deposition, etching, or cleaning. Next, according to operation  1202 , the substrate supporting apparatus may be centered with respect to a ring. In an embodiment, operation  1202  may be performed during an idle period of the substrate processing apparatus. In another embodiment, the substrate processing apparatus may perform operation  1202  and then have the idle period. Thereafter, the same process may be repeated. 
     As described above, an application target of the substrate processing method is not limited to one reactor for processing one substrate. In some examples, the substrate processing method may be used in a batch reactor (i.e., a plurality of reactors) that processes a plurality of substrates, that is, a batch of substrates at a time. 
       FIG.  18    schematically shows an example of a substrate processing method for periodically centering a substrate supporting apparatus in a plurality of reactors. For example, the period may be hours, days, or years. 
     First, in operation  1301 , one series of processing or a plurality of series of processing may be performed on a batch of substrates. The substrate processing may include deposition, etching, or cleaning. In general, a batch of substrates includes 25 substrates, but the disclosure is not limited thereto. For example, a batch of substrates may be 10 to 200 sheets, 50 to 150 sheets, or the like, depending on an operational plan of a device operator. 
     Next, according to operation  1302 , a substrate supporting apparatus may be centered with respect to a ring. In general, upon completion of processing of a batch of substrates, the substrate processing apparatus enters an idle period. In an embodiment, operation  1302  may be performed during this idle period. In another embodiment, after performing processing on a batch of substrates in operation  1301 , in operation  1302 , the substrate processing apparatus may perform centering of the substrate processing apparatus immediately, and may then have an idle period. In the idle period, an operation of forming a reactor atmosphere for the next batch may be performed. For example, a plasma stabilization operation may be performed for the next batch of plasma processing, as described in U.S. Pat. No. 9,972,490 to Applicant ASM. 
     In operation  1303 , one series of processing or a plurality of series of processing may be performed on another batch of substrates. Next, in operation  1304 , the substrate supporting apparatus may be centered with respect to a ring. 
     Thereafter, the same process may be repeated. 
       FIG.  19    is a view of a substrate processing apparatus according to embodiments including two or more reactors. 
     In  FIG.  19   , the substrate processing apparatus may include the alignment device  14  and an alignment device support module  61  at a lower portion of the substrate supporting apparatus  3 . An example of the alignment device  14  is schematically shown in  FIG.  20   . The alignment device  14  may implement centering of a substrate supporting apparatus with respective to a ring using an X-Y stage. For example, as described above, the substrate supporting apparatus may be moved in +X, −X, +Y, and −Y directions to implement the centering. In addition, the alignment device  14  may be connected to the controller  15  (in  FIG.  7   ), and may automatically align the substrate supporting apparatus by a command from the controller. In a variation, the alignment device  14  may manually align the substrate supporting apparatus. 
     In  FIG.  19   , the substrate processing apparatus may further include the alignment device support module  61  below the alignment device  14 . The alignment device support module  61  is shown schematically in  FIG.  21   . The alignment device support module  61  may include the drive motor  11  (in  FIG.  7   ) to move the substrate supporting apparatus in a vertical direction. 
       FIG.  20    schematically shows an example of the alignment device  14 . The alignment device  14  may include an insertion portion HH into which the substrate supporting apparatus  3  (of  FIG.  7   ) may be inserted. The alignment device  14  may further include a stretchable portion insertion portion BB on which the stretchable portion  12  (of  FIG.  7   ) may be mounted. In addition, the alignment device  14  may further include a cooler  2700 . The cooler  2700 , when the substrate supporting apparatus is inserted into the alignment device  14 , may prevent the alignment device  14  from being heated by the heated substrate supporting apparatus, thereby preventing elements such as an X-axis motor (not shown), a Y-axis motor (not shown), and the like from being heated. 
     According to the substrate processing method and the substrate processing apparatus of the disclosure, the uniformity of a film thickness may be improved by adjusting the distance between a substrate supporting apparatus and a ring. In addition, in the event of a mismatch between components due to a high temperature process of the substrate processing apparatus and thus de-centering of the substrate supporting apparatus, the substrate supporting apparatus may be centered with respect to the ring. In addition, according to the disclosure, the centering may be performed easily and quickly with only the alignment device  14  (of  FIG.  7   ) and the controller  15  (of  FIG.  7   ) without a separate diagnostic tool (e.g., a sensor) for measuring the distance between the substrate supporting apparatus and the ring. 
     It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the following claims.