Patent Publication Number: US-2012027953-A1

Title: Rotating Reactor Assembly for Depositing Film on Substrate

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119(e) to co-pending U.S. Provisional Patent Application No. 61/368,442, filed on Jul. 28, 2010, which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     1. Field of Art 
     The present invention relates to a rotating reactor assembly for performing atomic layer deposition. 
     2. Description of the Related Art 
     A conventional scan-type atomic layer deposition (ALD) apparatus deposits a single atomic layer on a substrate with linear motion of the substrate relative to the depositing apparatus or with linear motion of the depositing apparatus relative to the substrate. During the operation, the scan-type ADL apparatus injects precursors onto the substrate. For example, the bottom of the ALD apparatus has injectors for injecting precursor materials on the top surface of the substrate. The substrate may undergo multiple iterations of linear motion relative to the scan-type ALD apparatus to deposit multiple atomic layers on the substrate. 
     The speed of depositing a desired number of atomic layers to obtain an ALD film of a predetermined thickness depends on the linear moving speed of the substrate or the ALD apparatus. However, due to the limited speed and control constraints, various technical challenges are encountered when the relative linear speed between the substrate and the ALD apparatus exceeds a certain limit. 
     One way of increasing the speed of depositing multiple atomic layers is to increase the number of injector modules in the ALD apparatus. The scan-type ALD apparatus may include multiple injector modules or multiple scan-type atomic layer deposition apparatuses placed adjacent to each other so that a single linear movement of the substrate allows multiple atomic layers to be deposited on the substrate. However, the increased number of injector modules or the ALD apparatuses increases space requirement and also costs associated with the ALD apparatuses. 
     SUMMARY 
     Embodiments relate to a rotating reactor assembly including an injector rotor with a channel extending in along a rotational axis of the injector rotor and at least one injection hole connected to the channel. An intake port is provided in the rotating reactor assembly through which a material is introduced. As the injector rotor rotates, the channel is timely and/or periodically connected to the intake port such that the material is injected to a substrate through the at least one injection hole. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a rotating reactor assembly according to one embodiment. 
         FIG. 2A  is a cross-sectional view of the rotating reactor assembly of  FIG. 1 , taken along line A-A′, according to one embodiment. 
         FIG. 2B  is a perspective view of an injector rotor of  FIG. 2A , according to one embodiment. 
         FIG. 3A  is an exploded view of a rotating reactor assembly according to one embodiment. 
         FIG. 3B  is a bottom view of a rotating reactor assembly according to one embodiment. 
         FIG. 3C  is a top view of a rotating reactor assembly according to one embodiment. 
         FIGS. 4A through 4D  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. 
         FIGS. 5A through 5D  are diagrams illustrating deposition patterns obtained using a rotating reactor assembly according to one embodiment. 
         FIGS. 6A and 6B  are diagrams illustrating films deposited using a rotating reactor assembly, according to one embodiment. 
         FIGS. 7 through 9  are cross-sectional views of rotating reactor assemblies according to embodiments. 
         FIGS. 10A through 10E  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. 
         FIG. 11A  is a longitudinal cross-sectional view of a rotating reactor assembly according to one embodiment. 
         FIG. 11B  is a transverse cross-sectional view of a manifolding plate of the rotating reactor assembly of  FIG. 11A . 
         FIG. 12A  is a longitudinal cross-sectional view of a rotating reactor assembly according to one embodiment. 
         FIG. 12B  is a transverse cross-sectional view of a joint portion of an intake opening and a channel of the rotating reactor assembly of  FIG. 12A . 
         FIGS. 13A through 13C  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. 
         FIG. 14  is a cross-sectional view of a rotating reactor assembly according to one embodiment. 
         FIGS. 15A through 15E  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. 
         FIGS. 16A through 16C  are cross-sectional views of rotating reactor assemblies according to embodiments. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Embodiments are described herein with reference to the accompanying drawings. Principles disclosed herein may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. In the description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the features of the embodiments. 
     The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting of this 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. Furthermore, the use of the terms a, an, etc. does not denote a limitation of quantity, but rather denotes the presence of at least one of the referenced item. The use of the terms “first”, “second”, and the like does not imply any particular order, but they are included to identify individual elements. Moreover, the use of the terms first, second, etc. does not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. It will be further understood that the terms “comprises” and/or “comprising”, or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of at least one other features, regions, integers, steps, operations, elements, components, and/or groups thereof. 
     In the drawings, like reference numerals in the drawings denote like elements. The shape, size and regions, and the like, of the drawing may be exaggerated for clarity. 
       FIG. 1  is a perspective view of a rotating reactor assembly  110  according to one embodiment. A substrate  100  may move relative to a rotating reactor assembly  110 . For this purpose, the substrate  100  may be mounted on a support (not shown). The movement of the substrate  100  relative to the rotating reactor assembly  110  may be a linear or rotational motion, but is not limited thereto. Although an example process of performing deposition by moving the substrate  100  relative to the rotating reactor assembly  110  is described in this embodiment, in other embodiments, the substrate  100  may be fixed and the rotating reactor assembly  110  may move relative to the substrate  100 . While the substrate  100  passes through the rotating reactor assembly  110 , a film  120  including one or more atomic layers may be formed on the substrate  100 . 
     Materials such as a source precursor, a reactant precursor and a purge gas may be supplied from an external source (not shown) into the rotating reactor assembly  110 . The materials may be supplied through a conduit (not shown) connected to the rotating reactor assembly  110 . The supplied materials may be injected to the substrate  100  passing through the rotating reactor assembly  110  by the rotating reactor assembly  110 . The rotating reactor assembly  110  may include a housing  111  enclosing the rotating reactor assembly  110 , and excess materials may be discharged out of the rotating reactor assembly  110  through exhaust portions  112 ,  113 . 
     The rotating reactor assembly  110  according to one embodiment may be disposed in a deposition apparatus such as an ALD apparatus. The rotating reactor assembly  110  may operate at a pressure lower than the atmospheric pressure. For example, the rotating reactor assembly  110  may be operated in vacuum state. For this purpose, the pressure of the portion of the deposition apparatus where the rotating reactor assembly  110  is disposed may be controlled adequately according to a deposition process by the rotating reactor assembly  110 . And, the portion of the deposition apparatus where the rotating reactor assembly  110  is disposed may be filled with a material that does not react with the material (e.g., the source precursor, the reactant precursor, and the purge gas) injected to the substrate by the rotating reactor assembly  110 . For example, the apparatus may be filled with Ar, He, N 2  or H 2  gas. 
     The rotating reactor assembly  110  according to one embodiment may be disposed in plural numbers in one deposition apparatus. In this case, apparatuses for performing different semiconductor manufacturing processes may be provided in the space between the rotating reactor assemblies  110 . For example, a heating device for heat-treating the substrate or a plasma-generating device for treating the substrate with a plasma may be provided between one rotating reactor assembly  110  and the next rotating reactor assembly  110  in the ALD apparatus. As such, by providing other process-related apparatuses together with the rotating reactor assembly  110  according to one embodiment in the ALD apparatus, the flexibility of the semiconductor manufacturing process can be improved without significantly increasing the complexity and size of the ALD apparatus. 
       FIG. 2A  is a cross-sectional view of the rotating reactor assembly shown in  FIG. 1 , along line A-A′. The rotating reactor assembly  110  may include, among other components, an injector rotor  210 , a housing  220  enclosing the injector rotor  210  and side walls  230 ,  240 . All or part of the housing  220  and the side walls  230 ,  240  may be formed integrally, but the present invention is not limited thereto. 
     The injector rotor  210  may be installed in a cavity formed in the housing  220 . An opening  221  may be formed at the bottom portion of the housing  220 . The surface of the injector rotor  210  exposed through the opening  221  may be spaced apart from the nearest portion of the substrate  100  by a spacing H 1 . A material may be injected by the injector rotor  210  to the substrate therebelow through the opening  221  of the housing  220 . Excess material of the injected material may be pumped out of the rotating reactor assembly  110  through exhaust portions  235 ,  245  located between the housing  220  and the side walls  230 ,  240 . 
     The injector rotor  210  may rotate in the housing  220  at a predetermined angular speed. While the substrate  100  passes below the rotating injector rotor  210 , a film may be formed on the substrate  100  by the material injected by the injector rotor  210 . In one embodiment, the moving direction of the substrate  100  is the same as the rotating direction of the injector rotor  210 . That is to say, while the substrate  100  passes below the injector rotor  210 , the surface of the injector rotor  210  facing the substrate  100  may move in the same direction as the moving direction of the substrate  100 . However, in another embodiment, the moving direction of the substrate  100  may be opposite to the rotating direction of the injector rotor  210 . That is, while the substrate  100  passes below the injector rotor  210 , the surface of the injector rotor  210  facing the substrate  100  may move in a direction opposite to the moving direction of the substrate  100 . 
     The injector rotor  210  may have a channel and one or more injection hole(s) connected thereto. In one embodiment, the injector rotor  210  may have one or more first injection hole(s)  211  and one or more second injection hole(s)  212 . The one or more first injection hole(s)  211  may be connected to a first channel  213 . Similarly, the one or more second injection hole(s)  212  may be connected to a second channel  214 . The first channel  213  and the second channel  214  may extend in a longitudinal direction. In one embodiment, The first channel  213  and the second channel  214  extend parallel to the rotational axis of the injector rotor  210 . For example, if the injector rotor  210  has a cylindrical shape, the first channel  213  and the second channel  214  may be formed in the injector rotor  210  and extend along the length direction of the cylinder. 
     While the injector rotor  210  rotates, only the first channel  213  may be connected to a first intake port  250 , and the second channel  214  may be disconnected from the first intake port  250 . Likewise, only the second channel  214  may be connected to a second intake port  260 , and the first channel  213  may not be disconnected from the second intake port  260 . The first channel  213  and the first intake port  250  may be disposed in locations that are a first distance away from the rotational axis of the injector rotor  210 , and the second channel  214  and the second intake port  260  may be disposed in locations that are a second distance away from the rotational axis of the injector rotor  210 . That is, the first channel  213  and the first intake port  250  may be arranged on a circumference in a cross-section perpendicular to the length direction of the injector rotor  210 , and the second channel  214  and the second intake port  260  may be arranged on another circumference different therefrom. 
     The one or more first injection hole(s)  211  may be disposed in a first recess  215  formed on the surface of the injector rotor  210 . For example, the injector rotor  210  may have a cylindrical shape, and the first recess  215  may be formed on the bent side surface of the injector rotor  210 . Similarly, the one or more second injection hole(s)  212  may be disposed in a second recess  216  formed on the surface of the injector rotor  210 . For example, the first recess  215  and the second recess  216  may be formed in the shape of a rectangular parallelepiped formed on the surface of the injector rotor  210  along the length direction of the injector rotor  210 . However, the present invention is not limited thereto. 
     The one or more first injection hole(s)  211  and the one or more second injection hole(s)  212  may be arranged in a direction parallel to the rotational axis of the injector rotor  210 . The one or more first injection hole(s)  211  may be spaced from one another. And, the one or more second injection hole(s)  212  may be spaced from one another. Meanwhile, the one or more second injection hole(s)  212  may be spaced from the one or more first injection hole(s)  211 . 
     The rotating reactor assembly  110  may include one or more intake port(s) for injecting the material to the substrate. In one embodiment, the rotating reactor assembly  110  includes a first intake port  250  and a second intake port  260 . The first intake port  250  and the second intake port  260  may be connected to sources (not shown) supplying different materials. As the injector rotor  210  rotates, the first channel  213  may be connected to the first intake port  250  in accordance with the rotation speed of the injector rotor  210 , such that the material introduced through the first intake port  250  may be injected to the substrate  100  through the one or more first injection hole(s)  211 . Likewise, as the injector rotor  210  rotates, the second channel  214  may be connected to the second intake port  260  in accordance with the rotation speed of the injector rotor  210 , such that the material introduced through the second intake port  260  may be injected to the substrate  100  through the one or more second injection hole(s)  212 . 
     When the first recess  215  is located below the housing  220  as the injector rotor  210  rotates, the first channel  213  may be connected to the first intake port  250 . Then, a first material introduced through the first intake port  250  may be transferred through the first channel  213  and then injected through the one or more first injection hole(s)  211  to fill the first recess  215 . For example, the first material may be a source precursor for depositing an atomic layer, but is not limited thereto. Subsequently, as the injector rotor  210  rotates, the first material may be injected to the substrate  100 . 
     When the second recess  216  is located below the housing  220  as the injector rotor  210  further rotates, the second channel  214  may be connected to the second intake port  260 . As a result, a second material introduced through the second intake port  260  may be filled in the second recess  216 . The second material may be a reactant precursor for forming an atomic layer, but is not limited thereto. When the second recess  216  is already filled with a purge gas prior to the injection of the second material, the second material pushes out the purge gas and fills the second recess  216 . Subsequently, as the injector rotor  210  rotates further, the second material may be injected to the substrate  100 . 
     The opening  221  of the housing  220  may have a width W. And, the first recess  215  and the second recess  216  formed on the injector rotor  210  may have widths W 1  and W 2 , respectively. In one embodiment, the widths W 1  and W 2  of the first recess  215  and the second recess  216  are smaller than the width W of the opening  221  of the housing  220 . However, the present invention is not limited thereto. 
     In one embodiment, the housing  220  includes a channel  223  and one or more injection hole(s)  224  connected to the channel  223 . A purge gas may be injected between the injector rotor  210  and the housing  220  through the channel  223  and the one or more injection hole(s)  224 . For example, the purge gas may be Ar gas, but is not limited thereto. In one embodiment, the channel  223  and the one or more injection hole(s)  224  may be provided at the upper portion of the housing  220 , so that the purge gas may be injected downward to the injector rotor  210 . The injected purge gas may flow through a space between the injector rotor  210  and the housing  220  and be discharged through the opening  221  of the housing  220 . Subsequently, the purge gas may travel flow through a space between the bottom surface of the housing  220  and the substrate  100  and be discharged outward through the exhaust portions  235 ,  245 . 
     By passing the purge gas through the narrow gap between the substrate  100  and the housing  220 , an excess precursor material (e.g., a layer of precursor material physically (not chemically) adsorbed on the substrate  100 ) may be removed from the surface of the substrate  100 . Distances X 1  and X 2  from both ends of the opening  221  of the housing  220  to the adjacent exhaust portions  235 ,  245  along the moving direction of the substrate  100  and the corresponding heights z 1  and z 2  may be determined adequately depending on the properties of the film to be deposited. And, the purge gas may remove the excess material remaining in the first recess  215  and the second recess  216  of the injector rotor  210 , so as to prevent the materials injected through the first intake port  250  and the second intake port  260  from reacting with each other between the injector rotor  210  and the housing  220 . 
     The lower ends of the side walls  230 ,  240  may be spaced apart from the substrate  100  by a spacing z 0 . In one embodiment, the pressure inside the rotating reactor assembly  110  may be higher than the pressure outside the rotating reactor assembly  110 . As a result, a material may flow out of the rotating reactor assembly  110  through the gap between the lower ends of the side walls  230 ,  240  and the substrate  100 . Especially, a purge gas flowing out of the rotating reactor assembly  110  may act as a gas curtain which prevents impurities from influencing the deposition process by the rotating reactor assembly  110 . In one embodiment, a ferrofluid may be provided between the lower ends of the side walls  230 ,  240  and the substrate  100  in order to prevent the material from leaking out of the rotating reactor assembly  110 . 
       FIG. 2B  is a perspective view of the injector rotor of  FIG. 2A , according to one embodiment. The injector rotor  210 , the first channel  213  and the second channel  214  may extend along the rotational axis of the injector rotor  210 . The second recess  216  formed on the injector rotor  210  may be formed as a groove having a length L 2  along a direction parallel to the rotational axis of the injector rotor  210 . The length L 2  of the second recess  216  may be smaller than the length L 1  of the injector rotor  210 . As a result, clearance portions  2101 ,  2102  where a film is not deposited may be formed at both ends of the second recess  216  along a direction parallel to the rotational axis of the injector rotor  210 . The first recess  215  may also have a similar configuration as that of the second recess  216 . 
     In a film deposition process using the rotating reactor assembly described above with reference to  FIGS. 2A and 2B , the film deposition rate may be determined by various parameters related to the rotating reactor assembly. For example, the film deposition rate may be determined based on the rotation speed of the injector rotor  210 , the flow rate of the source precursor and the reactant precursor introduced through the first intake port  250  and the second intake port  260 , the flow rate of the purge gas introduced through the channel  223  of the housing  220 , the moving speed and direction of the substrate  100 , the spacing z 1 , z 2  between the substrate  100  and the lower end of the housing  220 , the spacing H 1  between the substrate  100  and the injector rotor  210 , the width W 1  and depth D 1  of the first recess  215  and the width W 2  and depth D 2  of the second recess  216  formed in the injector rotor  210 , the distance X 1 , X 2  from the both ends of the opening  221  of the housing  220  to the adjacent exhaust portions  235 ,  245 , or the like. 
       FIG. 3A  is an exploded view of the rotating reactor assembly according to one embodiment,  FIG. 3B  is a bottom view of the rotating reactor assembly according to one embodiment, and  FIG. 3C  is a top view of the rotating reactor assembly according to one embodiment. A rotating reactor assembly  110  may include, among other components, an injector rotor  210 , a housing  220  and covers  270 ,  280  provided at both ends of side walls  230 ,  240 . The cover  280  may have a first intake port  250  and a second intake port  260 . However, this is only exemplary. In another embodiment, one or more intake port(s) may be formed in the cover  270  or another portion of the rotating reactor assembly  110 . The rotating reactor assembly  110  may further comprise devices such as a sealing apparatus for preventing leakage of a material which is not illustrated in  FIG. 3A . 
       FIGS. 4A through 4D  are cross-sectional views of the rotating reactor assembly according to one embodiment in various phases. The rotating reactor assembly  110  in  FIGS. 4A through 4D  is the same as that of the rotating reactor assembly described above with reference to  FIGS. 2A and 2B , except that the housing  220  further comprises another one or more channel(s)  225  and injection hole(s)  226  respectively connected to the channel(s)  225 . 
     One channel  225  and one or more injection hole(s)  226  connected thereto may be provided at one end of the opening  221  of the housing  220 , and another channel  225  and one or more injection hole(s)  226  connected thereto may be provided at the other end of the opening  221  of the housing  220 . The function of the channel  225  and the one or more injection hole(s)  226  is the same as that of the channel  223  and the one or more injection hole(s)  224  described above. Therefore, a detailed description will be omitted. 
       FIG. 4A  is a cross-sectional view of the rotating reactor assembly according to one embodiment in a first phase. In the state where a first channel  213  and a second channel  214  are not respectively connected to a first intake port  250  and a second intake port  260 , only a purge gas injected through the injection holes  224 ,  226  of the housing  220  exists in the space between the injector rotor  210  and the housing  220 . The pressure of the purge gas injected through the injection holes  224 ,  226  may be larger than the pressure of a precursor injected through the intake ports  250 ,  260 . As a result, the purge gas injected through the injection holes  224 ,  226  may discharge a precursor remaining from a previous deposition stage by pushing it out to exhaust portions  235 ,  245 . 
       FIG. 4B  is a cross-sectional view of the rotating reactor assembly according to one embodiment in a second phase. As the injector rotor  210  rotates, a first recess  215  may face a substrate  100  passing below the rotating reactor assembly  110 . Then, the first channel  213  is connected to the first intake port  250 , and the material introduced through the first intake port  250  may be transferred through the first channel  213  and injected to the substrate  100  through one or more first injection hole(s)  211 . For example, the material introduced through the first intake port  250  may be a first precursor. The injected first precursor may be deposited on the surface of the substrate  100 , and molecules physisorbed to the surface of the substrate  100  may be removed by the purge gas injected through the injection holes  224 ,  226 . In this phase, a second recess  216  is aligned with the injection hole  224  formed on the housing  220 , such that the second recess  216  is filled with the purge gas. 
       FIG. 4C  is a cross-sectional view of the rotating reactor assembly  110  according to one embodiment in a third phase. As the injector rotor  210  rotates further from the phase illustrated in  FIG. 4B , the first channel  213  is separated from the first intake port  250 . The second channel  214  is not connected to the second intake port  260 . Accordingly, in this phase, the precursor is not supplied to the substrate  100 . The purge gas may be injected through the injection hole  226  of the housing  220 , and molecules physisorbed to the surface of the substrate  100  may be removed by the purge gas. 
       FIG. 4D  is a cross-sectional view of the rotating reactor assembly according to one embodiment in a fourth phase. As the injector rotor  210  rotates further from the phase illustrated in  FIG. 4C , the second recess  216  may face the substrate  100  as illustrated in  FIG. 4D . In this phase, the second channel  214  may be connected to the second intake port  260 , and the material introduced through the second intake port  260  may be transferred through the second channel  214  and injected to the substrate  100  through the one or more second injection hole(s)  212 . For example, the material introduced through the second intake port  260  may be a second precursor. The injected second precursor may react with the first precursor adsorbed in the surface of the substrate  100  to form a film on the substrate  100 . Meanwhile, molecules physisorbed on the surface of the substrate  100  may be removed by the purge gas injected through the injection holes  224 ,  226 . In this phase, the first recess  215  is aligned with the injection hole  224  formed on the housing  220 , such that the first recess  215  is filled with the purge gas. 
     When the injector rotor  210  rotates further from the fourth phase shown in  FIG. 4D , it returns to the first phase described above with reference to  FIG. 4A . Every time the injector rotor  210  rotates once, the first through fourth phases described referring to  FIGS. 4A through 4D  may proceed sequentially. This procedure may be performed repeatedly until a film of desired thickness is deposited. The state of the substrate in the first through fourth phases described referring to  FIGS. 4A through 4D  is summarized in Table 1. 
     
       
         
           
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Phase 
                 Substrate 
               
               
                   
               
             
            
               
                 First phase: Introduce first 
                 Surface of substrate covered with 
               
               
                 precursor (e.g., source 
                 chemisorbed source precursor 
               
               
                 precursor) to substrate 
                 molecules and excess physisorbed 
               
               
                   
                 source precursor molecules 
               
               
                 Second phase: Introduce purge 
                 Surface of substrate covered with 
               
               
                 gas (e.g., Ar gas) to substrate 
                 chemisorbed source precursor 
               
               
                   
                 molecules 
               
               
                 Third Phase: Introduce second 
                 Surface of substrate covered with 
               
               
                 precursor (e.g., reactant 
                 chemisorbed reactant precursor 
               
               
                 precursor) to substrate 
                 molecules and excess physisorbed 
               
               
                   
                 reactant precursor molecules 
               
               
                 Fourth phase: Introduce purge 
                 Physisorbed reactant precursor 
               
               
                 gas (e.g., Ar gas) to substrate 
                 molecules removed to obtain a 
               
               
                   
                 single ALD layer 
               
               
                   
               
            
           
         
       
     
       FIG. 5A  illustrates a pattern of molecules adsorbed on the substrate  100  when the moving speed of the substrate is excessively fast compared to the rotation speed of the injector rotor, according to one embodiment. If the moving speed of the substrate  100  is excessively fast compared to the rotation speed of the injector rotor, a source precursor layer  510  and a reactant precursor layer  520  are deposited alternatingly on the substrate  100 , and the source precursor layer  510  and the reactant precursor layer  520  are spaced apart from each other. Accordingly, reaction between the source precursor and the reactant precursor do not occur, and the atomic layer is not formed on the substrate  100 . 
       FIGS. 5B through 5D  show deposition patterns obtained using a rotating reactor assembly according to one embodiment when the rotation speed of the injector rotor is synchronized with the moving speed of the substrate. Referring to  FIG. 5B , since a source precursor layer and a reactant precursor layer are formed in the same region, a film  120  may be formed on the substrate  100  via the reaction between the source precursor and the reactant precursor. First, the reactant precursor layer  520  is deposited on the source precursor layer  510  as shown in  FIG. 5C . Then, the deposited reactant precursor may react with the source precursor to form single atomic layer  120  as shown in  FIG. 5D . 
       FIG. 6A  is a top view of a film formed on the substrate when the moving speed of the substrate is relatively slow as compared to the rotation speed of the injector rotor, and  FIG. 6B  is a transverse cross-sectional view of the film shown in  FIG. 6A . Referring to  FIGS. 6A and 6B , if the moving speed of the substrate is sufficiently slow, the source precursor and the reactant precursor may be injected to the substrate multiple times while the substrate passes below the rotating reactor assembly. Accordingly, a film  120  comprising multiple layers may be formed on the substrate while the substrate passes below the rotating reactor assembly. The number of the layers  120  depicted in  FIG. 6B  is only exemplary. When the moving speed of the substrate  100  is slower, a film comprising a larger number of layers  120  may be formed. That is, by controlling the moving speed of the substrate relatively to the rotation speed of the injector rotor of the rotating reactor assembly, the thickness of the film formed on the substrate may be controlled as desired. 
       FIG. 7  is a cross-sectional view of a rotating reactor assembly according to one embodiment. An injector rotor  210  of a rotating reactor assembly  110  according to this embodiment may further include one or more third channel(s)  217 . Each of the third channel(s)  217  may be connected to one or more third injection hole(s)  218 . Each of the third injection hole(s)  218  may be arranged to face a housing  220  in a third recess  219  formed on the surface of the injector rotor  210 . The rotating reactor assembly  110  may further include a third intake port  290  for providing a purge gas. When the third channel  217  becomes aligned with the third intake port  290  as the injector rotor  210  rotates, the purge gas introduced through the third intake port  290  may be transferred through the third channel  217  and injected to a substrate  100  through the one or more third injection hole(s)  218 . 
     The purge gas injected through the one or more third injection hole(s)  218  may act as a gas curtain which prevents a source precursor injected through one or more first injection hole(s)  211  and a reactant precursor injected through one or more second injection hole(s)  212  from being introduced into a gap between the injector rotor  210  and the housing  220 . For this, each of the third injection hole(s)  218  may be located adjacent to the first injection hole  211  and the second injection hole  212 . For example, the third recess  219  wherein the one or more third injection hole(s)  218  is (are) formed may be disposed such that it is adjacent to each end of a first recess  215  and a second recess  216 . 
     Referring to  FIG. 7 , when the injector rotor  210  rotates in a counter-clockwise direction, a source precursor may be injected through the one or more first injection hole(s)  211  to the substrate  100  passing below the injector rotor  210 , and then a purge gas may be injected through the one or more third injection hole(s)  218 . Accordingly, excess source precursor physisorbed on the surface of the substrate  100  may be pushed by the purge gas discharged to outside through an exhaust portion  245 . Such operation may be similarly applied to the injection of a reactant precursor through the one or more second injection hole(s)  212 . 
     In one embodiment, one or more partition(s)  700  for controlling the flow direction of the purge gas may be disposed in the third recess  219 . The partition(s)  700  may serve to prevent the backflow of the purge gas. However, this is only exemplary. In another embodiment, a device for controlling fluid flow other than the partition  700  may be disposed in the third recess  219  or a device for controlling fluid flow may not be disposed. 
       FIG. 8  is a cross-sectional view of a rotating reactor assembly according to one embodiment. A rotating reactor assembly  110  of  FIG. 8  is different from that of the embodiment shown in  FIG. 7  in that third recesses  219  are formed on both sides of a first recess  215  and on both sides of a second recess  216 . In each third recess  219 , a third channel  217  for injecting a purge gas and one or more third injection hole(s)  218  may be disposed. 
       FIG. 9  is a cross-sectional view of a rotating reactor assembly according to one embodiment. In a rotating reactor assembly  110  according to this embodiment, an injector rotor  210  may include a plurality of unit structures comprising a first channel  213  and one or more first injection hole(s)  211  connected thereto. Likewise, the injector rotor  210  may include a plurality of unit structures, each having a second channel  214  and one or more second injection hole(s)  212  connected to the second channel  214   o . And, third injection holes  218  for injecting a purge gas may be disposed adjacent to the first injection hole  211  and the second injection hole  212 . 
       FIGS. 10A through 10E  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. The rotating reactor assembly  110  according to this embodiment is similar to the rotating reactor assembly of  FIG. 4A  except that the cross-sectional shape of a first intake port  250 ′ and a second intake port  260 ′ is an arc, not a hole. For example, the cross-sectional shape of the first intake port  250 ′ and the second intake port  260 ′ may be an arc centered around the rotational axis of the injector rotor  210 . However, the shape of the intake port in the embodiment shown in  FIG. 10A  may also be applied to the rotating reactor assembly according to the embodiment shown in  FIG. 4A  as well as those according to other embodiments described herein. 
     Referring to  FIG. 10B , when a first channel  213  becomes aligned with the arc-shaped first intake port  250 ′, a source precursor may be injected through the first channel  213 . As shown in  FIG. 10C , the source precursor may be continuously injected into the first channel  213  until the first channel  213  moves to the other end of the first intake port  250 ′. Likewise, as shown in  FIG. 10D , a reactant precursor may be injected through a second channel  214 , when the second channel  214  becomes aligned with the arc-shaped second intake port  260 ′. As shown in  FIG. 10E , the reactant precursor may be continuously injected into the second channel  214  until the second channel  214  moves to the other end of the second intake port  260 ′. 
     In the rotating reactor assembly of  FIGS. 10A through 10E , the time during which the source precursor and the reactant precursor are injected through the first channel  213  and the second channel  214  may be determined by the length of the arc-shaped first intake port  250 ′ and second intake port  260 ′. For example, the length of the first intake port  250 ′ located relatively farther from the rotational axis of the injector rotor  210  may be longer than the length of the second intake port  260 ′ which is relatively closer to the rotational axis of the injector rotor  210 . In case the angular speed of the rotating injector rotor  210  is constant, the injection time of the source precursor may be made the same as the injection time of the reactant precursor by making the length of the first intake port  250 ′ located relatively farther from the rotational axis longer compared to the length of the second intake port  260 ′. However, this is only exemplary, and the length of the first intake port  250 ′ and the second intake port  260 ′ may be determined adequately depending on the properties of the layer to be deposited on the substrate  100 . 
     Although arc-shaped intake ports are described as examples in the embodiment described referring to  FIGS. 10A through 10E , the intake ports may have a different shape or configuration in other embodiment allowing the control of the time during which the injector rotor becomes aligned with the channel. 
       FIG. 11A  is a cross-sectional view of a rotating reactor assembly according to one embodiment.  FIG. 11B  is a front view of a manifolding plate of the rotating reactor assembly shown in  FIG. 11 , according to one embodiment. In the rotating reactor assembly according to this embodiment, an injector rotor  210  may be provided adjacent to a cover  280 , and the cover  280  may have a first intake port  250  and a second intake port  260  formed therein. In one embodiment, the cover  280  includes a manifolding plate  282  and a distribution plate  284 . And, an O-ring and/or a ferrofluid for preventing gas leakage may be provided between the manifolding plate  282  and the distribution plate  284  and/or between the distribution plate  284  and the injector rotor  210 . 
     The manifolding plate  282  may be coupled with a conduit  1110 ,  1120  which is connected to an external source (not shown). A material such as a source precursor or a reactant precursor supplied through the conduit  1110 ,  1120  may be supplied to the injector rotor  210  through an opening formed on the distribution plate  284 . The shape of the opening formed on the distribution plate  284  may be determined adequately depending on the time during which a source precursor, a reactant precursor and/or a purge gas is supplied, such as hole, arc, slot, or the like. And, the distribution plate  284  may be configured to be attachable to and detachable from the rotating reactor assembly. By inserting the distribution plate  284  having an opening with an adequate shape depending on the injection period and time of the source precursor, the reactant precursor and/or the purge gas to the rotating reactor assembly, the properties of the deposited layer can be controlled easily. 
       FIG. 12A  is a cross-sectional view of a rotating reactor assembly according to one embodiment.  FIG. 12B  is a transverse cross-sectional view of the portion of the rotating reactor assembly of  FIG. 12A  where an intake port is connected to an injector rotor, according to one embodiment. In a rotating reactor assembly according to this embodiment, an injector rotor  210  includes an intake opening  1200  formed on the surface of the injector rotor  210 . The intake opening  1200  may be provided on the outer circumference of the injector rotor  210  and may be connected through one or more channel(s)  1201 ,  1203  in the injector rotor  210  to a channel  213  through which a source precursor or a reactant precursor will be injected. As the injector rotor  210  rotates, the location of the intake opening  1200  provided on the outer circumference of the injector rotor  210  is changed. When the intake opening  1200  becomes aligned with an intake port  250 , a material injected through the intake port  250  may be supplied to the channel  213  through the intake opening  1200 . 
     In the embodiment shown in  FIG. 12B , the intake opening  1200  and the channel  213  are arranged to be perpendicular to each other in a direction perpendicular to the length direction of the injector rotor  210 . However, this is only exemplary. In another embodiment, the intake opening  1200  and the channel  213  may be arranged differently. 
     In the rotating reactor assembly according to the embodiment shown in  FIG. 12 , a ferrofluid  1203  may be provided in advance between the injector rotor  210  and a housing  220 . The ferrofluid  1203  serves to prevent the material injected through the intake port  250  from leaking out through the gap between the injector rotor  210  and the housing  220 . Since the flow of the ferrofluid  1203  is controlled by a magnetic field, the rotating reactor assembly according to this embodiment may further comprise a pole piece  1204 , a magnet  1205 , a magnetic bearing  1206 , or the like to control the flow of the ferrofluid  1203 . 
       FIGS. 13A through 13C  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. As shown in  FIG. 13A , when an intake opening  1200  of an injector rotor  210  is aligned with an intake port  250 , a material injected through the intake port  250  may be supplied to a channel  213  through the intake opening  1200 . Even if the injector rotor  210  rotates further as shown in  FIG. 13B , the material is continuously supplied to the channel  213  as long as the intake opening  1200  faces the intake port  250 . The supply of the material may be performed until the intake opening  1200  reaches the other end of the intake port  250 , as shown in  FIG. 13C . 
       FIG. 14  is a cross-sectional view of another rotating reactor assembly according to one embodiment. The configuration of the rotating reactor assembly according to the embodiment shown in  FIG. 14  is the same as that of the rotating reactor assemblies according to the embodiments described referring to  FIGS. 12 and 13 , except that an injector rotor  210  comprises a first channel  213 , a second channel  214 , a first intake opening  1200  and a second intake opening  1210 , and the rotating reactor assembly comprises a first intake port  250  and a second intake port  260 . 
     The first intake opening  1200  is connected to the first channel  213 . As the injector rotor  210  rotates and the first intake opening  1200  becomes aligned with the first intake port  250 , a material may be supplied to the first channel  213  through the first intake opening  1200 . Meanwhile, the second intake opening  1210  is connected to the second channel  214 . When the second intake opening  1210  is aligned with the second intake port  260  as the injector rotor  210  rotates, a material may be supplied to the second channel  214  through the second intake opening  1210 . 
       FIGS. 15A through 15E  are cross-sectional views of a rotating reactor assembly according to one embodiment in various phases. A rotating reactor assembly  110  according to this embodiment may further comprise a third intake port  255  and a fourth intake port  265  through which a purge gas is introduced in addition to a first intake port  250  through which a source precursor is introduced and a second intake port  260  through which a reactant precursor is introduced. The third intake port  255  may be arranged concentrically with the first intake port  250 . And, the fourth intake port  265  may be arranged concentrically with the second intake port  260 . In one embodiment, the cross-sectional shape of each of the first to fourth intake ports  250 ,  260 ,  255 ,  265  may be an arc centered around the rotational axis of an injector rotor  210 , but is not limited thereto. 
     Referring to  FIGS. 15B and 15C , while a first channel  213  is aligned with the first intake port  250 , a source precursor may be supplied through the first channel  213 . Referring to  FIGS. 15D and 15E , as the injector rotor  210  rotates further, the first channel  213  may pass the first intake port  250  and be aligned with the third intake port  255  disposed concentrically with the first intake port  250 . While the first channel  213  is aligned with the third intake port  255 , a purge gas may be supplied through the first channel  213 . Accordingly, purging by the purge gas may be carried out following the injection of the source precursor and, thus, excess source precursor physisorbed on a substrate  100  may be removed. 
     Although a process whereby injection of the source precursor and purging are carried out while the first channel  213  passes the first intake port  250  and the third intake port  255  was described referring to  FIGS. 15B through 15E , the injection of a reactant precursor and purging may be carried out similarly while a second channel  214  passes the second intake port  260  and the fourth intake port  265 . 
       FIG. 16A  is a cross-sectional view of a rotating reactor assembly according to one embodiment. In a rotating reactor assembly according to this embodiment, a housing  220  may include a plasma generator  1600  for supplying radicals formed by a plasma. In one embodiment, the plasma generator  1600  may comprise a channel  1601  through which a reactant gas for generating a plasma is injected, an internal electrode  1602  and an external electrode  1603 , and one or more injection hole(s)  1604  for supplying radicals formed by the plasma. The rotating reactor assembly according to this embodiment may comprise the plasma generator  1600  in singular or plural numbers. For example, the plasma generators  1600  may be disposed on both sides of the opening  221  of the housing  220 . However, the present invention is not limited thereto. 
     When the reactant gas is injected into the plasma generator  1600  through the channel  1601 , a voltage may be applied between the internal electrode  1602  and the external electrode  1603  to generate a plasma from the reactant gas between the internal electrode  1602  and the external electrode  1603 . The external electrode  1603  may be an outer wall enclosing the internal electrode  1602 . For example, at least a part of the housing  220  may be formed with a conducting material and a voltage may be applied thereto, so that the function of the external electrode  1603  can be exerted. However, this is only exemplary. In another embodiment, the external electrode  1603  may be provided as a separate electrode independently of the housing  220 . 
     In one embodiment, a direct current (DC) voltage may be applied between the internal electrode  1602  and the external electrode  1603 . For example, the DC voltage applied between the internal electrode  1602  and the external electrode  1603  may be from about 800 V to about 1.5 kV. Also, a DC pulse voltage with a frequency of about 500 kHz or lower may be applied between the internal electrode  1602  and the external electrode  1603 . 
     In one embodiment, the outer diameter of the internal electrode  1602  may be from about 3 to about 6 mm. And, the inner diameter of the external electrode  1603  may be from about 10 to about 20 mm. The reactant gas may be injected between the internal electrode  1602  and the external electrode  1603  configured as described above. The flow rate of the reactant gas may be about 5 to 100 sccm. And, the injection hole  1604  for supplying the plasma generated from the reactant gas may have a shape of a slit having a width of about 2 to 4 mm. 
     A radical-assisted ALD process may be performed on a substrate using the rotating reactor assembly according to the embodiment described referring to  FIG. 16A . Some examples of the radical-assisted ALD process that may be performed using the rotating reactor assembly according to this embodiment is described hereinafter. However, the process that may be performed using the rotating reactor assembly is not limited thereto. 
     1. Source as Followed by Ar Followed by Plasma (Radicals) Followed by Ar 
     First, while injecting Ar gas through the channel  223  and one or more injection hole(s)  224  formed at the upper portion of the housing  220 , a source precursor may be injected to a substrate  100  through a channel  213  and one or more injection hole(s)  211  formed on an injector rotor  210 . The source precursor may also be supplied by bubbling using the Ar gas. Alternatively, the source precursor may be supplied by vapor drawing or direct liquid injection (DLI). That is to say, the supply method is not particularly limited. In one embodiment, the source precursor may be trimethylaluminum (TMA, (CH 3 ) 3 Al) and an Al 2 O 3  film may be formed on the substrate  100  using the same. Alternatively, the source precursor may be dimethylamuninumhydride (DMAH) [(CH 3 ) 2 AlH] or methylethylaminoaluminum hydride [(AlN(CH 3 )(C 2 H 5 )H 2 )] and an AN film or an Al film may be formed on the substrate  100  using the same. 
     As the injector rotor  210  rotates, the source precursor is injected to the substrate  100 , and then the Ar gas is injected to the substrate  100 . The injected Ar gas may remove source precursor molecules or excess source precursor material physisorbed to the substrate  100 . Subsequently, radicals of a reactant precursor supplied by the plasma generator  1600  may be injected to the substrate  100 . For example, when an Al 2 O 3  film is desired to be formed, O 2  or N 2 O may be supplied to the plasma generator  1600  as the reactant precursor. And, when an AN film is desired to be formed, N 2  or NH 3  may be supplied to the plasma generator  1600  as the reactant precursor. And, when an Al film is desired to be formed, H 2  may be supplied to the plasma generator  1600  as the reactant precursor. Furthermore, Ar gas may be included in the gas supplied to the plasma generator  1600  for stabilizing the plasma. 
     The supply of the radicals by the plasma generator  1600  needs not necessarily be continuous. For example, after the injection of the source gas and the injection of the Ar gas to the substrate  100  are completed, a voltage may be applied to the plasma generator  1600  to supply radicals of the reactant precursor to the substrate. Then, after blocking power supply to the plasma generator  1600 , excess materials may be removed from the substrate  100  using the Ar gas. 
     2. Source as Followed by Ar as Followed by Plasma (Radicals) Followed by Ar* Followed by Ar 
     In one embodiment, after the injection of the source gas and the injection of the Ar gas to the substrate  100  are completed, the reactant precursor may be injected to the plasma generator  1600  before applying a voltage to the plasma generator  1600 , in order to prevent the source precursor from being introduced to the plasma generator  1600 . The reactant precursor supplied to the plasma generator  1600  is injected to the substrate  100 , and may form a film on the substrate by reacting with the source precursor on the substrate. After a predetermined time passes, a voltage may be applied to the plasma generator  1600  while supplying Ar gas to the plasma generator  1600 . As a result, argon plasma may be generated and injected to the substrate  100 . The argon plasma may be injected to the substrate  100  until the source precursor is injected again through the one or more injection hole(s)  211 . While the source precursor is injected, argon plasma may not be generated. 
     By treating the substrate  100  with Ar* (activated Ar or Ar radical), the density of the film formed on the substrate  100  may be improved or the bonding state of the molecules present on the surface of the substrate  100  may be changed. For example, the surface of the substrate  100  may be treated with Ar*, so that the bonding between the molecules on the surface of the film formed on the substrate  100  may be broken or the molecules may remain unoccupied or have dangling bonds until the source precursor is injected in the next stage. 
     Since Ar* has a very short lifetime, after the surface of the substrate  100  is treated with Ar*, Ar* may be converted back to Ar. After the conversion, Ar may act as the purge gas as described above. Therefore, following the surface of the substrate  100  with Ar*, purging by Ar gas is performed naturally. 
     3. Source as Followed by Ar as Followed by Ar* Followed by Plasma (Radicals) Followed by Ar* Followed by Ar 
     In one embodiment, Ar gas may be supplied to the plasma generator  1600  before the reactant precursor is supplied by the plasma generator  1600 . As a result, the substrate  100  is exposed first to Ar* before the reactant precursor is exposed to the radical. Subsequently, by changing the gas supplied by the plasma generator  1600  from the Ar gas to the reactant precursor, radicals of the reactant precursor may be injected to the substrate. Then, by changing the gas supplied by the plasma generator  1600  again to the Ar gas, Ar* may be injected to the substrate. 
       FIG. 16B  is a cross-sectional view of a rotating reactor assembly according to one embodiment. The rotating reactor assembly shown in  FIG. 16B  is similar to the rotating reactor assembly of  FIG. 16A , except that an injector rotor  210  includes a first channel  213  and a second channel  214  and further comprises one or more first injection hole(s)  211  and one or more second injection hole(s)  212 . The first channel  213  and the second channel  214  may be alternatingly connected to one intake port  250 . As a result, the same precursor may be injected through the one or more first injection hole(s)  211  and the one or more second injection hole(s)  212 . Accordingly, deposition rate can be improved since the amount of the precursor injected per revolution of the injector rotor  210  can be increased. 
       FIG. 16C  is a cross-sectional view of a rotating reactor assembly according to one embodiment. The rotating reactor assembly shown in  FIG. 16C  is similar to that of the rotating reactor assembly according to the embodiment described referring to  FIG. 16B , except that the rotating reactor assembly comprises a first intake port  250  and a second intake port  260 . As an injector rotor  210  rotates, the first intake port  250  may be connected to a first channel  213  and the second intake port  260  may be connected to a second channel  214  in accordance with the rotation speed of the injector rotor  210 . Accordingly, two different source precursors may be alternatingly injected to a substrate  100 . 
     For example, TMA may be injected through one or more first injection hole(s)  211  and tertamethylethylaminozirconium (TEMAZr, [(CH 3 )(C 2 H 5 )N] 4 Zr) may be injected through one or more second injection hole(s)  212 . In this case, an Al 2 O 3  layer formed via a reaction between the TMA and radicals injected by a plasma generator  1600  and a ZrO 2  layer formed via a reaction between the TEMAZr and the radicals injected by the plasma generator  1600  may be deposited alternatingly on the substrate  100 . 
     Although the present invention has been described above with respect to several embodiments, various modifications can be made within the scope of the present invention. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.