Patent Publication Number: US-11396702-B2

Title: Gas supply unit and substrate processing apparatus including the gas supply unit

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 15/802,154, filed Nov. 2, 2017, which claims the benefit of Korean Patent Application No. 10-2016-0152239, filed on Nov. 15, 2016 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein in their entireties by reference. 
    
    
     BACKGROUND 
     1. Field 
     One or more embodiments relate to a gas supply unit and a substrate processing apparatus including the gas supply unit, and more particularly, to a gas supply unit capable of controlling film deposition on a specific portion of a substrate, and a deposition apparatus including the gas supply unit. 
     2. Description of the Related Art 
     In a process of manufacturing a semiconductor device, as a circuit line width decreases, more precise process control has been required. In a film deposition process that is one of important semiconductor processes, various efforts to achieve high film uniformity have been made. 
     One of major factors for uniform film deposition is a gas supply unit. A showerhead method is employed for a common gas supply unit. The showerhead method has a merit of uniformly supplying a gas onto a substrate in a coaxial shape. However, a problem may occur when a gas supplied to a substrate is discharged, and thus the thickness of a film at an edge portion of the substrate and the thickness of a film at a center portion of the substrate are not uniform. 
     SUMMARY 
     One or more embodiments include a gas supply unit capable of controlling film deposition at an edge portion of a substrate, and a substrate processing apparatus including the gas supply unit. 
     One or more embodiments include a gas supply unit capable of forming a layer having a relatively uniform thickness considering a specific surface area of a stack structure, when a layer is formed on the stack structure of a substrate to be processed such as a semiconductor substrate or a display substrate, and a substrate processing apparatus including the gas supply unit. 
     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. 
     According to one or more embodiments, a substrate processing apparatus includes a partition configured to provide a gas supply channel, and a gas supply unit connected to the gas supply channel, wherein a gas flow channel communicating with the gas supply channel is formed in the gas supply unit, a first through-hole is formed to penetrate through at least a part of the partition, a second through-hole is formed to penetrate through at least a part of the gas supply unit, and the first through-hole communicates with the gas flow channel via the second through-hole, and the second through-hole is arranged between a center and an edge of the gas flow channel, and is arranged spaced apart from the edge. 
     The substrate processing apparatus may further include a radio frequency (RF) rod connected to the gas supply unit by penetrating through at least a part of the partition. 
     The gas supply unit may include a gas channel and a gas supply plate, and the gas flow channel may be formed between the gas channel and the gas supply plate. 
     A width of the gas flow channel may gradually decrease from the center toward a periphery. 
     The second through-hole may be arranged to face a stack structure of a substrate to be processed. 
     The second through-hole may penetrate in a perpendicular direction or an inclined direction with respect to the gas supply plate. 
     A buffer space may be formed between the first through-hole and the second through-hole, and a width of the buffer space may be greater than a width of the first through-hole and is greater than a width of the second through-hole. 
     The buffer space may be continuously formed along a circumference spaced apart a certain distance from a center of the gas supply channel. 
     The substrate processing apparatus may further include a susceptor configured to contact a lower surface of the partition. 
     The substrate processing apparatus may further include a first gas supplier connected to the gas supply channel, a second gas supplier connected to the first through-hole, and a controller configured to control the first gas supplier and the second gas supplier. 
     The controller may be further configured to independently control the first gas supplier and the second gas supplier. 
     According to one or more embodiments, a substrate processing apparatus includes a reactor wall, a first partition separating an inner space of the reactor wall into an upper space and a lower space, a second partition arranged spaced apart a certain distance from a center of the upper space, a third partition arranged between the reactor wall and the second partition, a gas supply channel extending from the upper space to the lower space, a gas supply unit connected to the gas supply channel, a first through-hole penetrating through the third partition, and a second through-hole communicating with the first through-hole and penetrating through at least a part of the gas supply unit, wherein the second through-hole is arranged between a center and an edge of the gas supply unit, and is arranged spaced apart from the edge. 
     The substrate processing apparatus may further include a gas supply plate arranged in the lower space, and a gas channel stacked on the gas supply plate and mechanically coupled to the gas supply plate, wherein a gas flow channel is formed between the gas channel and the gas supply plate. 
     The substrate processing apparatus may further include at least one radio frequency (RF) rod, wherein the RF rod is electrically connected to the gas channel. 
     The RF rod may be formed to penetrate through a portion of the first partition, the portion being arranged between the second partition and the third partition. 
     The substrate processing apparatus may further include a discharge path formed between the reactor wall and the third partition, and a third through-hole formed in the first partition and connecting the lower space to the discharge path. 
     According to one or more embodiments, a gas supply unit includes a gas channel providing a center injection hole, and a gas supply plate arranged under the gas channel, wherein a gas flow channel communicating with the center injection hole is formed between the gas channel and the gas supply plate, the gas channel may include a through-hole penetrating through an area between a center and an edge of the gas flow channel, and the through-hole is arranged spaced apart from the edge. 
     A position of the through-hole may be determined considering a specific surface area of a substrate to be processed. 
     The through-hole may be plurally arranged or continuously formed along a circumference spaced apart a certain distance from a center of the center injection hole. 
     The through-hole may be arranged or formed along a first circumference having a first diameter on a first surface of the gas channel, the through-hole may be arranged or formed along a second circumference having a second diameter on a second surface of the gas channel, and the first diameter and the second diameter may be identical to or different from each other. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic cross-sectional view of a gas supply unit according to an embodiment, and a substrate processing apparatus including the gas supply unit; 
         FIG. 2  is a schematic cross-sectional view of a gas supply unit according to another embodiment, and a substrate processing apparatus including the gas supply unit; 
         FIGS. 3 to 6  are cross-sectional views of gas supply units according to other embodiments; 
         FIG. 7  is a schematic cross-sectional view of a gas supply unit according to another embodiment, and a substrate processing apparatus including the gas supply unit; 
         FIGS. 8 to 11  are flowcharts for explaining methods of manufacturing a film by using a substrate processing apparatus, according to other embodiments; 
         FIGS. 12 and 13  are schematic cross-sectional views of substrate processing apparatuses according to other embodiments; 
         FIG. 14  is an enlarged cross-sectional view of a discharge portion of the substrate processing apparatus; 
         FIGS. 15 to 17  are schematic perspective views of reactors according to other embodiments and substrate processing apparatuses including the reactors; 
         FIGS. 18 and 19  schematically illustrate structures of reactors according to other embodiments; 
         FIGS. 20 and 21  schematically illustrate structures of back plates according to other embodiments; 
         FIGS. 22 to 24  are, respectively, a perspective view, a top view, and a bottom view of a gas channel included in the gas supply unit, according to an embodiment; 
         FIGS. 25 and 26  illustrate various embodiments of a fourth through-hole and a fifth through-hole penetrating through a back plate and a gas channel; and 
         FIGS. 27 and 28  are graphs showing a thickness of a SiO 2  film deposited on a substrate by a plasma-enhanced atomic layer deposition (PEALD) method in a reactor according to an embodiment. 
     
    
    
     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. 
     Embodiments are provided to further completely explain the present inventive concept to one of ordinary skill in the art to which the present inventive concept pertains. However, the present inventive concept is not limited thereto and it will be understood that various changes in form and details may be made therein without departing from the spirit and scope of the following claims. That is, descriptions on particular structures or functions may be presented merely for explaining embodiments of the present inventive concept. 
     In the following description, when a layer is described to exist on another layer, the layer may exist directly on the other layer or a third layer may be interposed therebetween. Also, the thickness or size of each layer illustrated in the drawings may be exaggerated for convenience of explanation and clarity. Like references indicate like constituent elements in the drawings. As used in the present specification, the term “and/or” includes any one of listed items and all of at least one combination of the items. 
     Terms used in the present specification are used for explaining a specific embodiment, not for limiting the present inventive concept. Thus, the expression of singularity in the present specification includes the expression of plurality unless clearly specified otherwise in context. Also, terms such as “comprise” and/or “comprising” may be construed to denote a certain characteristic, number, step, operation, constituent element, or a combination thereof, but may not be construed to exclude the existence of or a possibility of addition of one or more other characteristics, numbers, steps, operations, constituent elements, or combinations thereof. 
     In the present specification, terms such as “first” and “second” are used herein merely to describe a variety of members, parts, areas, layers, and/or portions, but the constituent elements are not limited by the terms. It is obvious that the members, parts, areas, layers, and/or portions are not limited by the terms. The terms are used only for the purpose of distinguishing one constituent element from another constituent element. Thus, without departing from the right scope of the present inventive concept, a first member, part, area, layer, or portion may refer to a second member, part, area, layer, or portion. 
     Hereinafter, the embodiments of the present inventive concept are described in detail with reference to the accompanying drawings. In the drawings, the illustrated shapes may be modified according to, for example, manufacturing technology and/or tolerance. Thus, the embodiment of the present inventive concept may not be construed to be limited to a particular shape of a part described in the present specification and may include a change in the shape generated during manufacturing, for example. 
       FIG. 1  is a schematic cross-sectional view of a gas supply unit according to an embodiment, and a substrate processing apparatus including the gas supply unit. 
     Referring to  FIG. 1 , the substrate processing apparatus according to the present embodiment may include a partition  110 , a gas supply unit  120 , a radio frequency (RF) rod  130 , and a discharge path  140 . Although an example of the substrate processing apparatus described in the present specification may include a deposition apparatus for a semiconductor or a display substrate, the present disclosure is not limited thereto. The substrate processing apparatus may be any apparatus needed to perform deposition of a material for forming a film, or may refer to an apparatus for uniformly supplying a source material for etching or polishing of a material. In the following description, for convenience of explanation, it is assumed that a substrate processing apparatus is a semiconductor deposition apparatus. 
     The partition  110  may be a constituent element of a reactor. In other words, a reaction space for processing, for example, deposition, etching, or polishing, of a substrate may be formed by the structure of the partition  110 . For example, the partition  110  may include a reactor sidewall and/or a reactor upper wall. A reactor upper wall portion of the partition  110  may provide a gas supply channel  150 , and a source gas, a purge gas, and/or a reactive gas may be supplied through the gas supply channel  150 . 
     The gas supply unit  120  may be connected to the gas supply channel  150 . The gas supply unit  120  may be fixed to the reactor. For example, the gas supply unit  120  may be fixed to the partition  110  through a fixed member (not shown). The gas supply unit  120  may be configured to supply a gas toward a target subject in a reaction space  160 . For example, the gas supply unit  120  may be a showerhead assembly. 
     A gas flow channel  170  communicating with the gas supply channel  150  may be formed in the gas supply unit  120 . The gas flow channel  170  may be formed between a gas channel  125  (upper portion) and a gas supply plate  127  (lower portion) of the gas supply unit  120 . Although the gas channel  125  and the gas supply plate  127  are illustrated in the drawing in a separate structure, the gas channel  125  and the gas supply plate  127  may be formed in an integrated structure. 
     In an embodiment, the gas flow channel  170  may have a width gradually decreasing from the center of the gas supply unit  120  toward a periphery thereof. The gas channel  125  may provide a center injection hole connected to the gas supply channel  150 . The center injection hole may be connected to the gas flow channel  170 . Accordingly, the gas flow channel  170  may be connected to the gas supply channel  150  via the center injection hole. 
     As described above, the gas supply channel  150  may be formed in the partition  110 . In addition to the gas supply channel  150 , a first through-hole  180  may be formed by penetrating through at least a part of the partition  110 . For example, the first through-hole  180  may penetrate through the reactor upper wall of the partition  110 . In an embodiment, the diameter of the first through-hole  180  may be smaller than the diameter of the gas supply channel  150 . 
     A second through-hole  185  may penetrate through at least a part of the gas supply unit  120 . For example, the second through-hole  185  may be connected to the gas flow channel  170  by penetrating through the gas channel  125 . Accordingly, the first through-hole  180  may be communicated with the gas flow channel  170  via the second through-hole  185 . 
     The second through-hole  185  may be arranged between a center and an edge of the gas flow channel  170 . In particular, the second through-hole  185  may be arranged spaced apart from the edge of the gas flow channel  170 . Film deposition of a particular portion of a substrate, that is, a portion corresponding to a portion where the second through-hole  185  is arranged, may be controlled according to the above positional structure of the second through-hole  185 . 
     For example, the gas supplied through the second through-hole  185  may affect the uniformity of a film deposited in a portion between the center and edge of a substrate. When the gas is a purge gas, the thickness of a film deposited in the portion between the center and edge of a substrate may decrease. When the gas is a reactive gas, the thickness of a film deposited in the portion between the center and edge of a substrate may increase. 
     As such, the present inventive concept may disclose the gas supply unit  120  that uniformly supplies a gas toward a substrate, and in particular, may provide a device to improve the uniformity of a film deposited on a portion between the center and edge of a substrate. 
     The showerhead assembly generally employs a structure of supplying a reactive gas through a center portion and discharging a residual gas through an edge portion. Accordingly, due to the above structure, the thickness of a film in the edge portion of a substrate and the thickness of a film at the center portion of the substrate may not be uniform. However, according to the present inventive concept, by additionally providing a separate gas supply path, a flow rate of a gas supplied between a center portion and an edge portion of the reaction space  160  may be controlled. The gas of a controlled flow rate may induce a promoting effect or a blocking effect in a peripheral portion of the reaction space  160 , and thus a source gas and a reactive gas supplied to the peripheral portion of a substrate may be controlled. Accordingly, the uniformity of a film in a particular portion between the center and the edge of a substrate may be controlled, and thus a film having a desired shape and desired uniformity may be deposited. 
     Furthermore, according to the present embodiment, it is possible to deposit a relatively uniform film on a stack structure of a semiconductor substrate that is a target subject to be processed. In the semiconductor substrate, through various deposition/etching processes, a stack pattern is formed in a first region and no such pattern is formed in a second region. In this case, a specific surface area of the first region is greater than a specific surface area of the second region. Accordingly, to deposit a uniform film on the semiconductor substrate, a more amount of a source gas and/or a reactive gas needs to be supplied to the first region than to the second region. According to the present inventive concept, in this case, the second through-hole  185  is arranged corresponding to the first region, that is, to face the stack structure of a substrate to be processed, the source gas and/or reactive gas may be additionally supplied to the first region. By doing so, the uniformity of the films deposited in the first region and the second region may be obtained. 
     In some embodiments, the second through-hole  185  may be arranged in the second region and a purge gas may be additionally supplied thereto. In this case, a relatively small amount of the source gas and/or the reactive gas may be supplied to the second region that is flat, and a relatively large amount of the source gas and/or the reactive gas may be supplied to the first region having a large specific surface area. Thus, the uniformity of the films deposited in the first region and the second region may be obtained. 
     The position of the second through-hole  185  may be determined considering the position of the stack structure of the substrate to be processed. As described above, the specific surface area of a region where the stack structure is formed is greater than the specific surface area of a region where the stack structure is not formed. Accordingly, the position of the second through-hole  185  according to the present inventive concept may be designed to offset irregularity in the film deposition due to a difference in the specific surface area. In other words, the position of a through-hole is determined considering the specific surface area of a substrate to be processed. 
     In some embodiments, the second through-hole  185  may be arranged at a plurality of positions along a circumference that is spaced apart a certain distance from the center of the center injection hole. In some embodiments, the second through-hole  185  may be continuously arranged along a circumference that is spaced apart a certain distance from the center of the center injection hole. In this case, the gas channel  125  may include a plurality of parts separated by the second through-hole  185 . 
     The second through-hole  185  may penetrate through the gas channel  125  in a perpendicular or incline direction with respect to the gas supply plate  127  (or the gas flow channel  170 ). For example, the second through-hole  185  may penetrate through the gas channel  125  with respect to an extension direction, that is, a horizontal direction of the gas supply plate  127 , at an angle of about 15° to about 45° toward the center of the gas supply plate  127 . In other words, by controlling a penetration angle of the second through-hole  185  penetrating through the gas channel  125 , the uniformity of a film, for example, a film of a particular portion on a substrate including the stack structure, may be controlled. 
     In an embodiment, the second through-hole  185  may penetrate through the gas channel  125  at an angle of about 30° with respect to the extension direction, that is, a horizontal direction of the gas supply plate  127 . In this case, the second through-hole  185  may be arranged or formed along a first circumference having a first diameter on a first surface, for example, an upper surface, of the gas channel  125 , and the second through-hole  185  may be arranged or formed along a second circumference having a second diameter on a second surface, for example, a lower surface, of the gas channel  125 , in which the first diameter and the second diameter may be different from each other. 
     In an embodiment, the position, shape, number, and angle of the second through-hole  185  may be adjusted according to the position and area of the stack structure of the substrate to be processed. As described above, the second through-hole  185  may be arranged facing a stack structure having a large specific surface area of the substrate to be processed. In this case, the diameter and/or number of the second through-hole  185  may be proportional to the area of the stack structure. Furthermore, the arrangement of the second through-hole  185  may be determined according to the shape of the stack structure. In addition, the angle or flow rate of the second through-hole  185  may also be designed according to the characteristics of the stack structure. 
     As such, by adjusting the number, shape, and arrangement position of the second through-hole  185 , and the type or flow rate of a gas supplied to the second through-hole  185 , the film uniformity may be accurately controlled and a film having a desired shape and desired uniformity may be deposited. 
     In some embodiments, a buffer space  190  may be further provided between the first through-hole  180  and the second through-hole  185 . The buffer space  190  may temporarily retain the gas supplied through the first through-hole  180  so to be uniformly supplied to the second through-hole  185 . Accordingly, the diameter or width of the buffer space  190  may be greater than the diameter or width of the first through-hole  180 , and also greater than the diameter or width of the second through-hole  185 . Furthermore, the buffer space  190  may be continuously formed along a circumference spaced apart a certain distance from the center of the gas supply channel  150 . 
     The substrate processing apparatus may further include a first gas supplier (not shown) connected to the gas supply channel  150  and a second gas supplier (not shown) connected to the first through-hole  180 . Furthermore, the substrate processing apparatus may further include a controller (not shown) configured to control the first gas supplier and the second gas supplier. In an embodiment, the controller may be further configured to independently control the first gas supplier and the second gas supplier. The controller&#39;s independent control operation of the gas supplier is described below in detail. 
     The substrate processing apparatus may further include the RF rod  130 . The RF rod  130  may be connected to the gas supply unit  120  by penetrating at least a part of the partition  110 . The RF rod  130  may be connected to an external plasma supplier (not shown). Although  FIG. 1  illustrates two RF rods as the RF rod  130 , the present inventive concept is not limited thereto and, one or more RF rods may be provided to improve uniformity of plasma power supplied to the reaction space  160 . 
     The substrate processing apparatus may further include a susceptor  200  that contacts a lower surface of the partition  110 . The susceptor  200  may be supported by a susceptor supporter  210 , and thus the susceptor supporter  210  may perform vertical and rotational motions. As the vertical motion of the susceptor supporter  210  enables the susceptor  200  to be separated from the partition  110  or to contact the partition  110 , the reaction space  160  may be opened or closed. 
     The substrate processing apparatus may further include a discharge portion (not shown). A residual gas remaining in the reaction space  160  after a chemical reaction with the substrate may be discharged by the discharge portion to the outside through the discharge path  140 . 
       FIG. 2  is a schematic cross-sectional view of the gas supply unit  120  according to another embodiment, and a substrate processing apparatus including the gas supply unit  120 . The gas supply unit  120  and the substrate processing apparatus according to the present embodiment may be a modified example of the gas supply unit  120  and the substrate processing apparatus according to the above-described embodiment. Redundant descriptions between the embodiments are omitted. 
     Referring to  FIG. 2 , the substrate processing apparatus according to the present embodiment may include the partition  110 , the gas supply unit  120  substantially horizontally located in the partition  110 , and the susceptor  200  located to substantially parallelly facing the gas supply unit  120  in the partition  110 . 
     The discharge path  140  provided in the partition  110  and connected to a vacuum pump may be used to vacuum-discharge the residual gas in the reaction space  160  in the partition  110 . 
     The gas supply unit  120  may be a showerhead, and a base of the showerhead may include a plurality of fine holes  220  that are formed to eject a raw gas. The showerhead may be connected to a raw gas supply tank via the gas supply channel  150 . An RF power may be electrically connected to the showerhead that functions as one electrode. 
     The susceptor  200  is supported by the susceptor supporter  12  and may function as an opposite electrode. A substrate to be processed, such as a semiconductor substrate, may be loaded on a surface of the susceptor  200 , and the substrate to be processed may be fixed by means of vacuum absorption. 
     Furthermore, as described above, the second through-hole  185  may penetrate through at least a part of an upper portion of the showerhead. Accordingly, the first through-hole  180  may communicate with the gas flow channel  170  of the showerhead via the second through-hole  185 . 
       FIGS. 3 to 6  are cross-sectional views of gas supply units according to other embodiments. The gas supply units according to other embodiments may be modified examples of the gas supply unit  120  of  FIG. 2 . Redundant descriptions between the embodiments are omitted in the following description. 
     Referring to  FIG. 3 , a lower surface of the showerhead may be formed to have a curvature. In detail, a distance between the showerhead that is an upper electrode and the subject to be processed may be the maximum at the center portion and may gradually decrease toward the edge portion. The through-hole  185  formed in the showerhead may be asymmetric with respect to the center of the showerhead. 
     Referring to  FIG. 4 , the through-hole  185  may include a plurality of sub-holes divided from a single main hole. Furthermore, in some embodiments, the diameters of the sub-holes may be set to be different from one another. For example, referring to  FIG. 5 , while a diameter or width w 1  of a first sub-hole formed in the edge portion may be relatively large, a diameter or width w 3  of a third sub-hole close to the center portion may be relatively small. Furthermore, a diameter or width w 2  of a second sub-hole between the first sub-hole and the third sub-hole may be formed such that w 1 &gt;w 2 &gt;w 3 . When a purge gas is supplied through the through-holes formed as above, a relatively large amount of the purge gas may be supplied to the edge portion and a relatively small amount of the purge gas may be supplied to the center portion. As a result, a relatively uniform film may be deposited on the substrate to be processed. 
     Referring to  FIG. 6 , the through-holes  185  may be arranged considering the specific surface area of a patterned structure of the substrate to be processed. For example, the patterned structure of the substrate to be processed may include a first region R 1  having a first specific surface area, a second region R 2  having a second specific surface area greater than the first specific surface area, and a third region R 3  having a third specific surface area greater than the second specific surface area. In this case, no through-hole may be formed in the first region R 1 , only one through-hole may be formed in the second region R 2 , and a plurality of through-holes may be formed in the third region R 3 . 
       FIG. 7  is a schematic cross-sectional view of a gas supply unit  120  according to another embodiment, and a substrate processing apparatus including the gas supply unit  120 . The gas supply unit and substrate processing apparatus according to the present embodiment may be modified examples of the gas supply unit  120  and substrate processing apparatus according to the above-described embodiment. Redundant descriptions between the embodiments are omitted in the following description. 
     Referring to  FIG. 7 , a first cover  240  and a second cover  250  including the partition  110  may form the reaction space  160  with the susceptor  200 . In detail, a lower portion of the reaction space  160  may be formed by the susceptor  200 , an upper portion of the reaction space  160  may be formed by the first cover  240 , and opposite lateral sides of the reaction space  160  may be formed by the second cover  250 . 
     When the substrate processing apparatus is a deposition apparatus, the first cover  240  may include a showerhead. The second cover  250  may include a reaction sidewall W and the discharge path  140 . 
     A discharge structure of the substrate processing apparatus may include a downstream discharge structure. In this state, the downstream discharge structure may be implemented by the second cover  250 . In this case, the gas used for deposition may be ejected toward the substrate to be processed via the showerhead of the first cover  240  and may be discharged downstream thereafter via the discharge path  140  of the second cover  250 . 
     Furthermore, as described above, the second through-hole  185  may penetrate through at least a part of the upper portion of the showerhead. Accordingly, the first through-hole  180  may communicate with the gas flow channel  170  of the showerhead via the second through-hole  185 . 
       FIGS. 8 to 11  are flowcharts for explaining methods of manufacturing a film by using a substrate processing apparatus, according to other embodiments. The film manufacturing methods according to other embodiments may be performed by using the gas supply unit and the substrate processing apparatus according to the above-described embodiments. Redundant descriptions between the embodiments are omitted in the following description. 
     Referring to  FIGS. 8 to 11 , the film manufacturing methods may include a first operation t 1  of supplying a source gas, a second operation t 2  of purging the source gas, a third operation t 3  of supplying a reactive gas, and a fourth operation t 4  of supplying plasma. The source gas, the reactive gas, and the plasma may be sequentially supplied. The purge gas may be temporarily supplied to the reaction space during the second operation. In some embodiments, the purge gas may be continuously supplied to the reaction space during the supply of the source gas, the reactive gas, and the plasma. 
     In addition, a fifth operation t 5  of purging residual gases may be performed after the first operation t 1  to the fourth operation t 4 . Furthermore, the first operation t 1  to the fourth operation t 4  (or the first operation t 1  to the fifth operation t 5 ) as one basic cycle may be repeated several times. 
     Referring to  FIG. 8 , during the third operation t 3 , the reactive gas may be supplied to the reaction space  160  via the gas supply channel  150  and the gas flow channel  170  formed at the center portion of the gas supply unit  120 . Furthermore, the reactive gas may be supplied to the reaction space  160  via the second through-hole  185  formed between the center and the edge of the gas supply unit  120 . Furthermore, during the third operation t 3 , a purge gas may be supplied to the second through-hole  185 . By adjusting a flow rate of the reactive gas and/or the purge gas supplied to the second through-hole  185 , the uniformity of a deposited film may be obtained. 
     Furthermore, referring to  FIG. 9 , during the first operation t 1 , the source gas may be supplied to the reaction space  160  via the gas supply channel  150  and the gas flow channel  170  formed at the center portion of the gas supply unit  120 . Furthermore, the source gas may be supplied to reaction space  160  via the second through-hole  185  formed between the center and the edge of the gas supply unit  120 . Furthermore, during the first operation t 1 , the purge gas may be supplied to the second through-hole  185 . By adjusting a flow rate of the source gas and/or the purge gas supplied to the second through-hole  185 , the uniformity of a deposited film may be obtained. 
     The supply of the purge gas, the reactive gas, and/or the source gas via the second through-hole  185  is to obtain the uniformity of a deposited film on the substrate to be processed. The uniformity of a film may signify forming a film having a uniform thickness with respect to a flat substrate, or forming a film having a uniform thickness with respect to a substrate on which some patterned structures are formed. In other words, the position, shape, and number of the second through-hole  185  may be designed considering not only the shape or arrangement of the constituent elements of a deposition apparatus, but also the specific surface area of a patterned structure formed on the substrate to be processed. 
     For example, as illustrated in  FIG. 10 , the second through-hole  185  may be arranged corresponding to the position of a particular stack structure formed on the substrate to be processed, and thus the reactive gas may be supplied to the corresponding stack structure of the substrate to be processed, via the second through-hole  185 . Furthermore, as illustrated in  FIG. 11 , the source gas may be supplied to the stack structure of the substrate to be processed, via the second through-hole  185 . 
     By using oversupply of the source gas and/or the reactive gas, relatively much deposition may be performed with respect to a stack structure having a large specific surface area. Although the oversupply of the reactive gas may serve as a factor for hindering the uniformity of film deposition with respect to a flat substrate, it may serve as a factor for improving the uniformity of film deposition with respect to a substrate, that is, an intermediate body, on which a stack structure having a large specific surface area is formed. 
       FIGS. 12 and 13  are schematic cross-sectional views of substrate processing apparatuses according to other embodiments. The substrate processing apparatuses according to other embodiments may be modified examples of the substrate processing apparatuses according to the above-described embodiments. Redundant descriptions between the embodiments are omitted in the following description. 
     Referring to  FIG. 12 , in a reactor  1 , a reaction space  18  is formed as a reactor wall  2  and a susceptor  25  perform face-contact and face-sealing with each other. A substrate is mounted on the susceptor  25  and a lower portion of the susceptor  25  is connected to a device (not shown) capable of ascending/descending to load/unload the substrate. 
     An inner space of the reactor wall  2  may be divided by a first partition  5  into a first region  3  and a second region  4 . The first region  3  and the second region  4  respectively correspond to an upper region and a lower region of the reactor  1 . The first region  3  may be divided by a second partition  6  into a third region  8  and a fourth region  13 . 
     Furthermore, the first region  3  may be divided by a third partition  7  into the fourth region  13  and a fifth region  14  In other words, as the third partition  7  is arranged between the reactor wall  2  and the second partition  6 , the fourth region  13  and the fifth region  14  may be formed. 
     A first through-hole  9  may be formed in the third region  8 . The first through-hole  9  penetrates through the first partition  5  and connects the third region  8  that is an upper space of the reactor  1  and the second region  4  that is a lower space of the reactor  1 . A first step  15  is formed between the first through-hole  9  and the third region  8 . 
     A sixth region  17  is formed between the second region  4  and the first partition  5 . The width of the first through-hole  9  penetrating through the third region  8  gradually increases toward the sixth region  17 . A space of the first through-hole  9  that increases toward the sixth region  17  may be filled with external air. The external air serves as an insulator during a plasma process, and thus generation of parasitic plasma in the space may be prevented. Furthermore, the sixth region  17  may further include a fourth partition  19 , and the fourth partition  19  may support a back plate  20 . 
     A gas inlet portion is inserted in the first through-hole  9 . The gas inlet portion may include a first gas inlet  26  and a flange  27 , and may further include a first gas supply channel  28  penetrating through the inside of the gas inlet portion. The first gas supply channel  28  penetrates through the first gas inlet  26  and the flange  27  and extends to the second region  4 . A sealing member such as an O-ring may be inserted in a coupling surface between the first gas inlet  26  and the flange  27 , and thus the first gas supply channel  28  may be isolated from the external air. A first gas supply path  29  and a second gas supply path  30  are connected to the first gas inlet  26  to supply a gas used for processing a substrate. For example, a source gas, a reactive gas, and a purge gas used for an atomic layer deposition process are supplied to the reaction space  18  via the first gas supply path  29 , the second gas supply path  30 , and the first gas supply channel  28 . The flange  27  may be formed of an insulator and may prevent leakage of plasma power during the plasma process. 
     The reactor  1  may further include a second through-hole  10  that penetrates through one surface of the third partition  7 . The second through-hole  10  is connected to the second region  4  by sequentially penetrating through the third partition  7  and the first partition  5 . An upper portion of the second through-hole  10  is coupled to a second gas inlet  31 . A sealing member such as an O-ring is inserted in a coupling surface between the second through-hole  10  and the second gas inlet  31 , and thus intrusion of the external air may be prevented. The source gas, the reactive gas, or the purge gas may be supplied through the second gas inlet  31  and the second through-hole  10 . As described above, the second through-hole  10  may be plurally provided. 
     The back plate  20 , a gas channel  21 , and a gas supply plate  22  may be sequentially arranged between the first partition  5  and the reaction space  18 . The gas supply plate  22  and the gas channel  21  may be coupled by using a coupling member. The gas channel  21  and the first partition  5  may be coupled by using another coupling member. 
     For example, the gas channel  21  and the first partition  5  may be coupled through the back plate  20 . As a result, the back plate  20 , the gas channel  21 , and the gas supply plate  22  may be sequentially stacked on the fourth partition  19  protruding from the first partition  5 . The gas supply plate  22  may include a plurality of holes for supplying a gas to a substrate (not shown) in the reaction space  18 . For example, a gas supply unit including the gas channel  21  and the gas supply plate  22  may be a showerhead, and in another example, the gas supply unit may be a device for uniformly supplying a material for etching or polishing an object. 
     A gas flow channel  24  is formed between the gas channel  21  and the gas supply plate  22 . A gas supplied through the first gas supply channel  28  may be uniformly supplied to the gas supply plate  22  by the gas flow channel  24 . A width of the gas flow channel  24  may gradually decrease from a center portion toward a peripheral portion thereof. 
     A third through-hole  23  may be formed in one surface of the back plate  20  and the gas channel  21 . A second step  16  may be formed between the back plate  20 , the gas channel  21 , and the third through-hole  23 . According to the present inventive concept, the third through-hole  23  may penetrate through center portions of the back plate  20  and the gas channel  21 , and the flange  27  of the gas inlet portion may be inserted in the first step  15  and to the second step  16 . 
     A sealing member such as an O-ring may be inserted between the flange  27  and the second step  16 , between the first partition  5  and the back plate  20 , and/or between the back plate  20  and the gas channel  21 . Accordingly, isolation from the external air may be obtained. 
     The reactor  1  may further include a fourth through-hole  11  penetrating through one surface of the back plate  20 , and a fifth through-hole  12  penetrating through one surface of the gas channel  21 . The fourth through-hole  11  and the fifth through-hole  12  may be connected to the second through-hole  10 . Accordingly, the gas supplied through the second through-hole  10  is supplied to the gas flow channel  24 . 
     The fifth through-hole  12  may penetrate through the gas channel  21  in a direction perpendicular to the gas supply plate  22 , or may penetrate through the gas channel  21  in an inclined direction as illustrated in  FIG. 12 . Furthermore, the penetration direction may lead toward the inside of the gas flow channel  24  or the outside thereof. Furthermore, the fifth through-hole  12  may be arranged between the center and the edge of the gas flow channel  24 , or arranged spaced apart from the edge. Alternatively, the position of the fifth through-hole  12  may be determined to correspond to the position of a patterned structure having a large specific surface area of the substrate to be processed. 
     The fourth through-holes  11  and/or the fifth through-holes  12  may be spaced apart a certain distance from a center line of the back plate  20  and the gas channel  21  and may form a plurality of through-holes in a horizontal direction. Alternatively, the fourth through-holes  11  and/or the fifth through-holes  12  may form a plurality of through-holes in a vertical direction while mainlining a certain distance toward a center line of the back plate  20  and the gas channel  21 . In the fourth through-hole  11  and/or the fifth through-hole  12 , the interval between the through-holes may be adjusted according to a desired process. 
     A buffer space  38  may be further formed between the second through-hole  10  and the fourth through-hole  11 . The buffer space  38  may retain the gas supplied through the second through-hole  10  so to be uniformly supplied to the fourth through-hole  11 . In some embodiments, the buffer space  38  may be formed between the fourth through-hole  11  and the fifth through-hole  12 . 
     A first discharge portion  32  is formed in the reactor wall  2  of the reactor  1 . The first discharge portion  32  may include a first discharge hole  33  and a first discharge channel  34 . The first discharge portion  32  is connected to the fifth region  14  via the first discharge hole  33  penetrating through the first partition  5 . 
     An upper portion of the fifth region  14  may be coupled to a discharge path cover  36 , forming a discharge path. A sealing member such as an O-ring is inserted in a coupling surface between the fifth region  14  and the discharge path cover  36 , thereby isolating the discharge path from the external air. Furthermore, one surface of the discharge path cover  36  may include a gas outlet  35 . The gas outlet  35  may be connected to a discharge pump (not shown) to discharge the gas. 
     An upper portion of the fourth region  13  of the reactor  1  may be coupled to an upper cover  37  for safety. The upper cover  37  may protect an RF distribution plate  39  from the outside. 
       FIG. 13  is a cross-sectional view of the reactor  1  viewed in a different direction. Referring to  FIG. 13 , in addition to the gas supply channel  28  of  FIG. 12 , at least one sixth through-hole  43  connected to the second region  4  by penetrating through another surface of the first partition  5  may be formed in the first partition  5  of the reactor  1 . The sixth through-hole  43  may be arranged between the second partition  6  and the third partition  7 . 
     A coupling member  40  may be inserted in the sixth through-hole  43 , and thus the gas channel  21  and the first partition  5  may be mechanically coupled to each other by the coupling member  40 . The back plate  20  may include a hole in one surface thereof, through which the coupling member  40  passes. The back plate  20  with the gas channel  21  may be mechanically coupled to the first partition  5 . The coupling member  40  may be a conductive body and may be a screw. 
     A support member  41  is inserted around the coupling member  40 , and the support member  41  is formed of an insulating body. Accordingly, the coupling member  40  and the first partition  5  may be electrically insulated from each other by the support member  41 , and thus the leakage of plasma power during the plasma process may be prevented. 
     The gas channel  21  and the gas supply plate  22  may be formed of a conductive body. Accordingly, the gas channel  21  and the gas supply plate  22  may serve as an electrode to transfer the plasma power during the plasma process plasma. 
     The flange  27 , the back plate  20 , and the support member  41  may be formed of an insulating body. Accordingly, the plasma power may be prevented from being leaked through the reactor wall  2  via the first partition  5 . Furthermore, by filling the first through-hole  9  and the sixth region  17  around the flange  27  with the external air, generation of parasitic plasma in the space may be prevented. 
     The gas channel  21  and the gas supply plate  22  arranged in a lower region (the second region  4 ) may be coupled to each other by a separate coupling member  42 . The coupling member  42  may be formed of a conductive body and may be a screw. In some embodiments, the gas channel  21  and the gas supply plate  22  included in gas supply unit may be integrally formed. 
       FIG. 14  is an enlarged cross-sectional view of a discharge portion of the substrate processing apparatus. Referring to  FIG. 14 , the discharge portion may include the first discharge portion  32  and a second discharge portion  44 . The first discharge portion  32  may include the first discharge hole  33  and the first discharge channel  34 . The second discharge portion  44  may include a second discharge hole  45  and a second discharge channel  46 . The first and second discharge holes  33  and  45  may penetrate through the first partition  5 . Furthermore, the first and second discharge holes  33  and  45  may connect the discharge path, that is, the fifth region  14 , and the discharge channels  34  and  46 . 
     In the reaction space  18 , the residual gas left after a chemical reaction with the substrate is discharged through the first and second discharge portions  32  and  44 . Most residual gas may flow to a region “A” via a discharge gap  48 . Then, the residual gas in the region “A” may pass through the first discharge portion  32  and may be discharged to the fifth region  14  that is a discharge path. 
     The gas confined to a region “B” that is a blind spot next to the gas channel and the gas supply plate may be discharged to the fifth region  14  that is a discharge path through the second discharge portion  44 . The diameters of the first discharge hole  33  and the second discharge hole  45  may be identical to or different from the diameters of the first discharge channel  34  and the second discharge channel  46 , respectively. By appropriately adjusting the ratio of the diameters of the first discharge hole  33 , the second discharge hole  45 , the first discharge channel  34 , and/or second discharge channel  46 , discharge efficiency at around the edge portion of the substrate may be controlled and the uniformity of a film may be adjusted accordingly. Furthermore, by adjusting the size of the discharge gap  48 , the discharge efficiency and the uniformity of a film may be controlled. 
       FIGS. 15 to 17  are schematic perspective views of reactors according to other embodiments and substrate processing apparatuses including the reactors. The substrate processing apparatus according to the present embodiment may be modified examples of the substrate processing apparatuses according to the above-described embodiments. Redundant descriptions between the embodiments are omitted in the following description. 
     Referring to  FIG. 15 , the reactor according to the present embodiment may further include a protection cover  50 , in addition to the first gas inlet  26 , the gas outlet  35 , and the discharge path cover  36 . The protection cover  50  is a protection cover to protect an RF delivery plate  52 . 
       FIGS. 16 and 17  illustrate that the protection cover  50  is removed. Referring to  FIGS. 16 and 17 , the RF delivery plate  52  is connected to the RF distribution plate  39 . The RF distribution plate  39  is electrically connected to a plurality of RF rods  54 . In an embodiment, for the uniform supply of RF power, the RF rods  54  may be symmetrically arranged with respect to the center of the gas channel  21 , for example, the center of the first gas inlet  26 . 
     An upper portion of the RF delivery plate  52  may be connected to an RF generator (not shown). A lower portion of the RF delivery plate  52  may be connected to the RF distribution plate  39 . The RF distribution plate  39  may be connected to the RF rods  54 . 
     Accordingly, the RF power generated by the RF generator is delivered to the gas channel  21  via the RF delivery plate  52 , the RF distribution plate  39 , and the RF rods  54 . The gas channel  21  is mechanically connected to the gas supply plate  22 , and the gas channel  21  and the gas supply plate  22  altogether may serve as RF electrodes. 
     At least one of the RF rods  54  may be installed in the reactor. The RF rods  54  may be arranged to penetrate through a portion of the first partition  5  of  FIG. 12  arranged between the second partition  6  of  FIG. 12  and the third partition  7  of  FIG. 12 . In an additional embodiment, as illustrated in  FIG. 17 , at least two of the RF rods  54  may be arranged, and the RF rods  54  may be symmetrically arranged with respect to the center of the reactor. The symmetric arrangement may enable the RF power to be uniformly supplied to the RF electrodes  21  and  22 . 
     In some embodiments, a cartridge heater (not shown) may be installed above the reactor wall  2  to heat the reactor wall. A plurality of cartridge heaters may be symmetrically arranged, and thus a uniform temperature gradation of the reactor wall  2  may be achieved. 
       FIGS. 18 and 19  schematically illustrate structures of reactors according to other embodiments. The reactors according to the present embodiments may be formed to have a perspective view ( FIG. 18 ) and a bottom view ( FIG. 19 ) 
     Referring to  FIGS. 18 and 19 , the second partition  6  may be arranged spaced apart a certain distance from the center of the upper space of the reactor wall  2 . The third partition  7  may be arranged between the sidewall of the reactor wall  2  and the second partition  6 . The gas supply channel  28  of  FIG. 12  extending from the upper space to the lower space may be provided by the structure of the second partition  6 . 
     The fourth partition  19  may contact an upper surface of the back plate  20  of  FIG. 12  to support the back plate  20 . 
     The coupling member  40  and the support member  41  may be inserted in a screw hole  56 . Accordingly, the gas channel  21  of  FIG. 12  and the back plate  20  of  FIG. 12  may be mechanically connected to the first partition  5  of  FIG. 12 . 
     The RF rods  54  are inserted in a plurality of RF rod holes  58  and electrically connected to the gas channel  21 . 
     A discharge path is formed in the fifth region  14 , and the first discharge hole  33  and the second discharge hole  45  may be respectively connected to the first discharge channel  34  of  FIG. 14  and the second discharge channel  46  of  FIG. 14 , forming a discharge portion. 
     The width of the first through-hole  9  may gradually increase toward the sixth region  17  of  FIG. 12 . The space of the sixth region  17  may be filled with the external air and may serve as an insulating body during the plasma process. Accordingly, the generation of parasitic plasma in the space formed by the first through-hole  9  may be prevented. 
       FIGS. 20 and 21  schematically illustrate structures of the back plates  20  according to other embodiments. The reactors according to the present embodiments may have a back plate to be formed to have a perspective view ( FIG. 20 ) and a bottom view ( FIG. 21 ). 
     The back plate  20  is located between the first partition  5  of  FIG. 12  and the gas channel  21  of  FIG. 12 . Furthermore, the back plate  20  formed of an insulating body may serve as an insulator to isolate the first partition  5  of  FIG. 12  from the gas channel  21  and the gas supply plate  22 , which are the RF electrodes, during the plasma process. 
     The fourth through-holes  11  may be plurally formed spaced apart a certain distance from the center of the back plate  20  in upper/lower surface of the back plate  20 . The fourth through-holes  11  may receive a gas from the second through-hole  10  of  FIG. 12  and supply the gas to the fifth through-hole  12  of  FIG. 12  penetrating through the gas channel  21  of  FIG. 12 . The third through-hole  23  is located at a center portion of the back plate  20 , and the flange  27  of  FIG. 12  is inserted in the third through-hole  23 . 
       FIGS. 22 to 24  are, respectively, a perspective view, a top view, and a bottom view of the gas channel  21  included in the gas supply unit, according to an embodiment. 
     The gas channel  21  may include a plurality of fifth through-holes  12  arranged spaced apart a certain distance from the center portion of the gas channel  21 . 
     Referring to  FIG. 23 , the positions of the fifth through-holes  12  in the upper surface of the gas channel  21  may correspond to the positions of the fourth through-holes  11  of the back plate  20  illustrated in  FIGS. 20 and 21 . 
     The fifth through-holes  12  formed in the gas channel  21  may penetrate through the gas channel  21  in a perpendicular direction or in an inclined direction. 
     For example, referring to  FIG. 23 , the fifth through-holes  12  may be arranged or formed along a first circumference having a first diameter d on a first surface of the gas channel  21 . Furthermore, referring to  FIG. 24 , the fifth through-holes  12  may be arranged or formed along a second circumference having a second diameter d′ on a second surface of the gas channel  21 . In an example, the first diameter d may be greater than the second diameter d′. However, the present inventive concept is not limited thereto, and it may be that d=d′ or d≠d′. 
       FIG. 25  illustrate various embodiments of the fourth through-hole  11  and the fifth through-hole  12  penetrating through the back plate  20  and the gas channel  21 . 
     As illustrated in  FIG. 25 , the fifth through-hole  12  penetrating through the gas channel  21  may penetrate in a perpendicular direction or an inclined direction with respect to the gas supply plate  22 . When the fifth through-hole  12  penetrates through the gas supply plate  22  in an inclined direction, the fifth through-hole  12  may lead toward the inside of the gas flow channel  24  or the outside thereof. Although it is not illustrated, the fourth through-hole  11  is not limited to the shape that extends vertically. 
       FIG. 26  illustrates that the second through-hole  10 , the fourth through-hole  11 , and the fifth through-hole  12  penetrate through the third partition  7 , the first partition  5 , the back plate  20 , and the gas channel  21 , according to another embodiment. 
     As illustrated in  FIG. 26 , each of the second gas inlet  31 , the second through-hole  10 , the buffer space  38 , the fourth through-hole  11 , and the fifth through-hole  12  is plurally provided and a plurality of gases are supplied to the gas flow channel  24  via the second gas inlets  31 . For example, the source gas, the reactive gas, and the purge gas may be supplied through the respective inlets. 
     The gas supplied to the gas flow channel  24  via the second through-hole  10 , the fourth through-hole  11 , and the fifth through-hole  12  may be supplied to an edge region of the reaction space  18  via an edge portion under the gas supply plate  22 , or to a region between the center portion and the edge portion of the reaction space  18 . As a result, the uniformity or characteristics of a film formed in an edge region (edge portion) of the substrate to be processed or in a specific peripheral portion between the center portion and the edge region of the substrate may be selectively controlled. 
     For example, the uniformity of a film deposited in the edge region of the substrate or in a region between the center portion and the edge portion of the substrate may be selectively controlled according to a flow rate of the gas supplied through the second, fourth, and fifth through-holes  10 ,  11 , and  12 , and a degree of inclination of the fifth through-hole  12  penetrating through the gas channel  21 . Furthermore, due to these factors, a uniformity deviation of a film deposited at the center and edge portions of the substrate may be reduced or controlled. 
     For example, a film having a minimum uniformity deviation between the center portion and the edge portion of the substrate may be deposited. In another example, a film having a concave shape, in which the edge portion of the substrate is thicker than the center portion thereof, may be deposited, or a film having a convex shape, in which the center portion of the substrate is thicker than the edge portion thereof, may be deposited. The gas supplied through the second through-hole  10 , the fourth through-hole  11 , and the fifth through-hole  12  may be an inert gas. In some embodiments, the gas may be the reactive gas and/or the source gas participating in the formation of a film. 
       FIGS. 27 and 28  are graphs showing a thickness of a SiO 2  film deposited on a substrate by a plasma-enhanced atomic layer deposition (PEALD) method in a reactor according to an embodiment. The graphs show the effect of the gas supplied through the second through-hole  10 , the fourth through-hole  11 , and the fifth through-hole  12  on the uniformity of a film, in particular, the uniformity of a film deposited at the edge portion of the substrate. 
     The horizontal axis of the graphs denotes a distance of 150 mm to the left and right from the center of the wafer when the diameter of the substrate is 300 mm. The vertical axis of the graphs denotes the thickness of a film. In the present embodiment, the effect is evaluated by setting the angle of the fifth through-hole  12  penetrating through the gas channel  21  to 30° and varying a gas flow rate. 
     
       
         
           
               
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 1st through-hole 
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Source 
                   
                   
                 2nd thru-hole 
                 RF 
                   
               
               
                 carrier Ar 
                 Purge Ar 
                 O2 
                 Edge gas 
                 power 
                 Pressure 
               
               
                 (sccm) 
                 (sccm) 
                 (sccm) 
                 (sccm) 
                 (W) 
                 (Torr) 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 1000 
                 3500 
                 200 
                 Ar 0~1000 
                 400 
                 2 
               
               
                 1000 
                 3500 
                 200 
                 O2 0~500 
                 400 
                 2 
               
               
                   
               
            
           
         
       
     
     As shown in Table 1, through the first through-hole (main hole) that is the gas supply channel, Ar of 1000 sccm was supplied as a source carrier and Ar of 3500 sccm was supplied as a purge gas, and O 2  of 200 sccm may be supplied as a reactive gas continuously for an entire process period (Accordingly, a total flow rate is 4,700 sccm). Plasma of 400 watt was supplied and a pressure of 2 torr was maintained in a reaction space during the process. 
     Oxygen was activated only when plasma is supplied and reacted with source molecules on the substrate. Accordingly, the oxygen serves as a purge gas when plasma is not supplied. Accordingly, oxygen may serve as a reactive purge gas in the present process. 
     The gas supplied through the second through-hole may be Ar or O 2 . The gas may be continuously supplied for the entire process period. The flow rate of the gas may be appropriately controlled according to a desired film uniformity around the substrate. 
     The inventive concept according to the above-described embodiments can be summarized as follows.
         First operation of continuously supplying a source gas, a purge gas, and a reactive purge gas through a first through-hole   Second operation of continuously supplying at least one of the purge gas and the reactive purge gas through a second through-hole   Third operation of applying plasma   The first operation and the second operation may be simultaneously performed, whereas the third operation may be temporarily performed while the first operation and the second operation are performed.       

     The first through-hole corresponds to the gas supply channel  28  of  FIG. 12 , and the second through-hole corresponds to the through-holes  10 ,  11 , and  12  of  FIG. 12  penetrating through at least a part of the gas supply unit. 
     As illustrated in  FIG. 27 , it may be seen that, as the flow rate of the Ar gas supplied through the second through-hole increases, the thickness of the film deposited at the edge portion of the substrate decreases. Also, as illustrated in  FIG. 28 , it may be seen that, as the flow rate of the oxygen gas supplied through the second through-hole increases, the thickness of the film deposited at the edge portion of the substrate increases. In other words, by inducing and controlling a blocking effect on a peripheral portion of the substrate with respect to the source gas and the reactive gas supplied to a peripheral portion of the reaction space, uniformity of a film on the substrate may be controlled. 
     The embodiment of the present inventive concept may not be construed to be limited to a particular shape of a part described in the present specification and may include a change in the shape generated during manufacturing, for example. 
     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 as defined by the following claims.