Patent Publication Number: US-2021193440-A1

Title: Substrate processing apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     A claim for priority under 35 U.S.C. § 119 is made to Korean Patent Application No. 10-2019-0169528 filed on Dec. 18, 2019, in the Korean Intellectual Property Office, the entire contents of which are hereby incorporated by reference. 
     BACKGROUND 
     Embodiments of the inventive concept described herein relate to a substrate treating apparatus, more particularly, a substrate treating apparatus using a plasma. 
     Plasma corresponds to an ionized gas comprising ions, radicals, electrons, and the like. The plasma is generated by very high temperature, strong electric fields, or radio frequency electromagnetic fields (RF Electromagnetic Fields). To manufacture semiconductor elements, various processes are performed such as ashing or etching to remove a thin film on a substrate using a plasma. A film on a substrate is ashed or etched through physical collision or chemical reaction with ions and radical particles contained the plasma. 
     In general, the plasma is generated in a chamber. A process gas is supplied into the chamber. The process gas supplied into the chamber is excited as the plasma by electromagnetic field generated in the chamber. The plasma collides with the chamber. The chamber is etched by colliding with the plasma. By this etching, foreign matters like particles are generated in the chamber. To minimize generating the foreign matters in the chamber, a method of forming a coating film on inside walls of the chamber is suggested. The coating film minimizes a direct reaction between the plasma and the inside walls of the chamber. But the general coating film can be easily damaged by a heat stress caused by the plasma having high temperature and by physical collision by the plasma. 
     On the other hand, etching the inside walls of the chamber or generating the foreign matters in the chamber are more often in an Inductively Coupled Plasma apparatus than a Capacitively Coupled Plasma apparatus. The CCP apparatus comprises an upper electrode and a lower electrode. And an electric field is generated between the upper electrode and the lower electrode. The plasma is generated between the upper electrode and the lower electrode both having the electric field. The generated plasma moves along a direction of the electric field which generated between the upper electrode and the lower electrode. That is, the plasma of the CCP apparatus often collides with two electrodes (the upper electrode and the lower electrode) not with the inside walls of the chamber. But the ICP apparatus has a plasma reaction chamber. The plasma reaction chamber is surrounded by an antenna coil. An alternating current which flows through the antenna coil and generates the electric field inside the plasma reaction chamber. The generated electric field generates the plasma. The plasma of the plasma reaction chamber moves toward one end and an opposite end of the antenna coil. A movement of the plasma comprises the movement toward inside walls of the chamber. That is, a collision between the plasma and the inside walls of the chamber in the ICP apparatus is stronger than a collision between the plasma and the inside walls of the chamber in the CCP apparatus. In addition, the collision in the ICP apparatus is more frequent than the CCP apparatus. 
     SUMMARY 
     Embodiments of the inventive concept provide a substrate treating apparatus. 
     In addition, embodiments of the inventive concept provide a substrate treating apparatus capable of minimizing a generation of foreign matters when inside walls of a chamber react with a plasma. 
     In addition, embodiments of the inventive concept provide a substrate treating apparatus capable of making a lifetime of the plasma chamber longer. 
     In addition, embodiments of the inventive concept provide a substrate treating apparatus capable of minimizing a damage of a coating film covering the inside walls of the plasma chamber, and capable of minimizing detachment of the coating film from the inside walls of the plasma chamber. 
     The inventive concept may be embodied in many different forms, and should not be construed as being limited to the embodiments set forth herein. The inventive concept and methods of accomplishing the same may be understood more readily by reference to the following detailed description of embodiments and the accompanying drawings. 
     Embodiments of the inventive concept provide a substrate processing apparatus. The substrate treating apparatus comprises a process treating unit providing a treating space performed treating the substrate; a plasma generating unit generating the plasma by discharging a process gas, and supplying the plasma to the treating space. The plasma generating unit provides a plasma chamber having a plasma generating space; an antenna wound to surround the plasma chamber multiple times outside the plasma chamber; a first coating film covering inside walls of the plasma chamber and comprising yttrium fluoride (YF3). 
     According to an exemplary embodiment, a second coating film covering the inside walls of the plasma chamber and comprising yttrium oxide (Y2O3) may be further provided. 
     According to an exemplary embodiment, the second coating film may be provided on the inside walls of the plasma chamber, and the first coating film may be provided on the second coating film. 
     According to an exemplary embodiment, when viewed from a front cross-section of the plasma chamber, when it comes to a thickness of the first coating film, the thickness of an upper area and a lower area of the plasma chamber is thicker than a central area of the plasma chamber. 
     According to an exemplary embodiment, in the entire inside walls of the plasma chamber, the sum of the thicknesses of the first coating film and the second coating film may be the same. 
     According to an exemplary embodiment, when viewed from a front cross-section of the plasma chamber, the first coating film may be provided to the upper area and the lower area among the upper area, the lower area, and a central area of the plasma chamber, and the second coating film may be provided to the central area. 
     According to an exemplary embodiment, the antenna is an ICP antenna, one end of the antenna may be connected to a power source applying a power to the antenna, and an opposite end of the antenna may be grounded. 
     According to an exemplary embodiment, when viewed from a front cross-section of the plasma chamber, each height of the one end and the opposite end of the antenna corresponds to the upper area and the lower area respectively of the plasma chamber. 
     According to an exemplary embodiment, the plasma generating unit comprises a gas supply unit supplying a process gas to the plasma generating space, and the process gas may comprise fluorine and/or hydrogen. 
     According to an exemplary embodiment, the plasma chamber may be formed of a material comprising aluminum oxide (Al2O3). 
     According to an exemplary embodiment, the plasma generating unit is arranged below the plasma chamber and may further comprise a diffusion chamber having a diffusion space for diffusing the plasma generated in the plasma chamber. 
     In addition, the inventive concept provides an apparatus for treating the substrate using the plasma. The apparatus for treating the substrate using the plasma comprises a chamber; a gas supply unit supplying process gas into the chamber; a plasma source generating the plasma in the chamber; a first coating film covering the inside walls of the chamber; and a second coating film covering the inside walls of the chamber and provided in a material different from the first coating film. 
     According to an exemplary embodiment, the second coating film may be provided on the inside walls of the chamber, and the first coating film may be provided on the second coating film. 
     According to an exemplary embodiment, when viewed from a front cross-section of the plasma chamber, when it comes to a thickness of the first coating film, the thickness of the upper area and the lower area of the plasma chamber is thicker than the central area of the plasma chamber. 
     According to an exemplary embodiment, in the entire inside walls of the chamber, the sum of the thicknesses of the first coating film and the second coating film may be the same. 
     According to an exemplary embodiment, when viewed from a front cross-section of the plasma chamber, the first coating film may be provided to the upper area and the lower area among the upper area, the lower area, and a central area of the plasma chamber, and the second coating film may be provided to the central area. 
     According to an exemplary embodiment, the chamber is a plasma chamber for generating the plasma, and at the outside the plasma chamber, the antenna is wound multiple times on the plasma chamber. 
     According to an exemplary embodiment, the antenna is an ICP antenna, one end of the antenna may be connected to a power source applying a power to the antenna, and an opposite end of the antenna may be grounded. 
     According to an exemplary embodiment, the first coating film comprises yttrium fluoride (YF3), and the second coating film comprises yttrium oxide (Y2O3). 
     According to an exemplary embodiment, the chamber may be formed of a material comprising aluminum oxide (Al2O3). 
     According to an exemplary embodiment, the process gas comprises Fluorine and/or Hydrogen. 
     According to an exemplary embodiment, the inventive concept provides a substrate treating apparatus capable of efficiently treating a substrate. 
     In addition, according to an exemplary embodiment, the inventive concept can minimize a foreign matter which is generated when inside walls of a chamber react with a plasma. 
     In addition, according to an exemplary embodiment, the inventive concept can extend a life span of the plasma chamber. 
     In addition, according to an exemplary embodiment, the inventive concept can minimize a damage of a coating film covering inside walls of a plasma chamber, or detachment of a coating film from the inside walls of the plasma chamber. 
     The inventive concept and methods of accomplishing the same may be understood more readily by reference to the following detailed description of embodiments and the accompanying drawings. However, the inventive concept may be embodied in many different forms, and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this inventive concept will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, and the inventive concept will only be defined by the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The above and other objects and features will become apparent from the following description with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures unless otherwise specified, and wherein: 
         FIG. 1  schematically shows a substrate treating apparatus of the inventive concept. 
         FIG. 2  shows a substrate treating apparatus performing a plasma treating process of a process chamber of the  FIG. 1 . 
         FIG. 3  shows a plasma chamber according to an embodiment of the inventive concept. 
         FIG. 4  shows plasma flow generated from the plasma chamber of  FIG. 3 . 
         FIG. 5  shows a plasma chamber according to another embodiment of the inventive concept. 
         FIG. 6  shows plasma flow generated from the plasma chamber of  FIG. 5 . 
         FIG. 7  shows a plasma chamber according to another embodiment of the inventive concept. 
         FIG. 8  shows plasma flow generated from the plasma chamber of  FIG. 7 . 
         FIG. 9  shows a plasma chamber according to another embodiment of the inventive concept. 
         FIG. 10  shows plasma flow generated from the plasma chamber of  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, the inventive concept and methods of accomplishing the same may be understood more readily by reference to the following detailed description of embodiments and the accompanying drawings. However, the inventive concept may be embodied in many different forms, and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this inventive concept will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, and the inventive concept will only be defined by the appended claims. 
     Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein. The term used herein describes the embodiment of the present disclosure and not be limited to the present disclosure. 
     As used herein, the singular forms “a”, “an”, and “the” are intended to include plural referents as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” and/or various conjugational forms of this verb, such as “comprisal”, “comprising”, “comprised”, do not preclude the presence or addition of one or more other constructions, components, devices, steps, actions. 
     The term “and/or” in this description refers to each of the configuration or to various combinations thereof. 
     The term used herein “part”, which processes at least one function or operation, for example, may mean software devices and hardware devices such as FPGA, or ASIC. However, “part” does not be limited by software or hardware. “part” may be composed of an addressable storage medium, or one or more processors running thereof. According to one exemplary embodiment of the inventive concept, “part” may include devices such as software devices, object-oriented software devices, class devices, and processes, functions, attributes, procedures, sub-routines, segments of program codes, drivers, firmware, microcode, circuits, data, databases, data structure, tables, arrays, and variables. Functions from devices and “part” may be separately performed by the plurality of devices and “part”, or be combined with additional devices. 
     Hereinafter, embodiments of the inventive concept are described with reference to  FIG. 1  to  FIG. 10 . 
       FIG. 1  schematically shows a substrate treating apparatus of the inventive concept. Referring to  FIG. 1 , a substrate treating equipment  1  has an equipment front end module (EFEM)  20  and a treating module  30 . The EFEM  20  and the treating module  30  are arranged in a direction. 
     The EFEM  20  has a load port  10  and a transfer frame  21 . The load port  10  is arranged in front of the EFEM  20  along a first direction  11 . The load port  10  has a plurality of support parts  6 . Each support part  6  is arranged in parallel along a second direction  12 , and a carrier  4  (e.g. a cassette player, FOUP) is mounted. The carrier receives a substrate ‘W’ to be processed and a substrate ‘W’ processed. The transfer frame  21  is arranged between the load port  10  and the treating module  30 . The transfer frame  21  comprises a first transfer robot  25 , the first transfer robot is arranged inside the transfer frame  21  and transfers the substrate ‘W’ between the load port  10  and the treating module  30 . The first transfer robot  25  moves along a transfer rail  27  installed along the second direction  12 , and the first transfer robot  25  transfers the substrate ‘W’ between the carrier  4  and the treating module  30 . 
     The treating module  30  comprises a load lock chamber  40 , a transfer chamber  50 , and a process chamber  60 . 
     The load lock chamber  40  is adjacently arranged to the transfer frame  21 . In one example, the load lock chamber  40  is arranged between the transfer chamber  50  and the EFEM  20 . Before the substrate ‘W’ to be processed is transferred to the process chamber  60  or the substrate ‘W’ processed is transferred to the EFEM  20 , the load lock chamber  40  provides a space where the substrate ‘W’ stands by. 
     The transfer chamber  50  is adjacently arranged to the load lock chamber  40 . When viewed from above, the transfer chamber  50  is a polygon. Referring to  FIG. 1 , when viewed from above, the transfer chamber  50  is a pentagon. At the outside of the transfer chamber  50 , the load lock chamber  40  and a plurality of process chambers  60  are arranged along a perimeter of the transfer chamber  50 . A passage (not shown) where the substrate ‘W’ is introduced and withdrawn is formed at each side walls of the transfer chamber  50 , the passage (not shown) connects the transfer chamber  50  and the load lock chamber  40  or connects process chambers  60 . Each passage has a door (not shown) which opens and closes the passage to seal the inside of the transfer chamber. A second transfer robot  53  is arranged inside of the transfer chamber  50 . The second transfer robot  53  transfers the substrate ‘W’ between the load lock chamber  40  and the process chambers  60 . The second transfer robot  53  transfers an untreated substrate ‘W’ which is stood by in the load lock chamber  40  to the process chamber  60 , or transfers a treated substrate ‘W’ to the load lock chamber  40 . And the second transfer robot  53  transfers the substrate ‘W’ among process chambers  60  for providing the substrate ‘W’ sequentially to the plurality of process chambers  60 . Like  FIG. 1 , when the transfer chamber  50  is a pentagon, the load lock chamber  40  is arranged at a side wall of the transfer chamber  50  which is adjacent to the EFEM  20 , and process chambers  60  are arranged sequentially at the other wall. The transfer chamber  50  may have various shape according to a requirement of a process module other than the above shape. 
     The process chambers  60  are arranged along a perimeter of the transfer chamber  50 . A plurality of the process chambers  60  may be provided. In each process chamber  60 , a process treatment of the substrate ‘W’ is performed. In the process chamber  60 , the substrate ‘W’ is treated by receiving from the second transfer robot  53 , and the treated substrate ‘W’ is provided to the second transfer robot  53 . The process treatment of each process chamber  60  may be different. Hereinafter, a substrate treating apparatus  1000  performing a plasma treating process will be described. 
       FIG. 2  shows a substrate treating apparatus performing a plasma treating process of a process chamber of the  FIG. 1 . Referring to  FIG. 2 , a substrate treating apparatus  1000  performs a predetermined process on the substrate ‘W’ using the plasma. For example, the substrate treating apparatus  1000  may etch or ash a thin film on the substrate ‘W’. The thin film may comprise a polysilicon film, a silicon oxide film, and a silicon nitride film. In addition, the thin film may be a native oxide film or a chemically generated oxide film. 
     The substrate treating apparatus  1000  have a process treating unit  200 , a plasma generating unit  400 , and an exhaust unit  600 . 
     The process treating unit  200  provides a treating space  212  in which a substrate ‘W’ is placed and the treating space  212  treats the substrate ‘W’. The plasma generating unit  400  discharges the process gas to generate the plasma, and supplies the plasma to the treating space  212  of the process treating unit  200 . The exhaust unit  600  discharges the process gas remaining in the process treating unit  200  and/or the reacted by-products generated in the substrate treating process to the outside, and the exhaust unit  600  maintains a pressure in the process treating unit  200  at a set pressure. 
     The process treating unit  200  may comprise a housing  210 , a support unit  230 , and a baffle  250 . 
     The housing  210  may have the treating space  212  therein, which performs the substrate treating process. An upper portion of the housing  210  is opened, and an opening (not shown) may be formed on side walls of the housing  210 . The substrate ‘W’ enters into the housing  210  via the opening (not shown). A door (not shown) which is kind of an open and close member may open and close the opening (not shown). In addition, an exhaust hole  214  is formed on a bottom surface of the housing  210 . The process gas and/or by-products in the treating space  212  may be exhausted to the outside via the exhaust hole  214 . The exhaust hole  214  may be connected to the configuration of the exhaust unit  600 , which will be described hereinafter. 
     The support unit  230  supports the substrate ‘W’ in the treating space  212 . The support unit  230  may comprise a support plate  232 , and a support shaft  234 . The support plate  232  supports the substrate ‘W’ in the treating space  212 . The support plate  232  is supported by the support shaft  234 . The support plate  232  is connected to an external power source and generates static electricity by the applied power. The electrostatic force of static electricity may fix the substrate ‘W’ to the support unit  230 . 
     The support shaft  234  may move an object. For example, the support shaft  234  may move the substrate ‘W’ up and down. For example, the support shaft  234  may be coupled to the support plate  232 , and may move the support plate  232  up and down to move the substrate ‘W’. 
     The baffle  250  is positioned above the support unit  230  to face the support unit  230 . The baffle  250  may be arranged between the support unit  230  and the plasma generating unit  400 . The plasma generated from the plasma generating unit  400  may pass through a plurality of holes  252  formed in the baffle  250 . 
     The baffle  250  allows the plasma entering the treating space  212  to be uniformly supplied to the substrate ‘W’. The holes  252  formed in the baffle  250  are provided in through-holes provided from the upper surface to the lower surface of the baffle  250 , and the holes  252  may be uniformly formed in each area of the baffle  250 . 
     The plasma generating unit  400  may be positioned at the upper portion of the housing  210 . The plasma generating unit  400  generates the plasma by discharging the process gas, and supplies the generated plasma to the treating space  212 . The plasma generating unit  400  may comprise a plasma chamber  410 , a gas supply unit  420 , a power supply unit  430 , and a diffusion chamber  440 . 
     An upper and a lower surface of the plasma chamber  410  may be opened. The plasma chamber  410  may be container having opened upper and lower surfaces. The plasma chamber  410  may be cylindrical shaped container having opened upper and lower surfaces. The plasma chamber  410  may have a plasma generating space  412 . In addition, a material of the plasma chamber  410  may comprise aluminum oxide (Al2O3). The upper surface of the plasma chamber  410  may be sealed by a gas supply port  414 . The gas supply port  414  may be connected to the gas supply unit  420 . The process gas may be supplied to the plasma generating space  412  through the gas supply port  414 . The gas supplied to the plasma generating space  412  may be introduced into the treating space  212  through the baffle  250 . 
     The gas supply unit  420  may supply a process gas. The gas supply unit  420  may be connected to the gas supply port  414 . The process gas supplied by the gas supply unit  420  may comprise fluorine and/or hydrogen. 
     The power supply unit  430  applies RF power to the plasma generating space  412 . The power supply unit  430  may be a plasma source that excites a process gas in the plasma generating space  412  to generate a plasma. The power supply unit  430  may comprise an antenna  432 , and a power source  434 . 
     The antenna  432  may be an inductively coupled plasma (ICP) antenna. The antenna  432  may be provided in a coil shape. The antenna  432  may be wound multiple times on the plasma chamber  410  outside the plasma chamber  410 . The antenna  432  may be wound multiple times in a spiral shape on the plasma chamber  410  outside the plasma chamber  410 . The antenna  432  may be wound on the plasma chamber  410  in an area corresponding to the plasma generating space  412 . When viewed from a front cross section of the plasma chamber  410 , a height of one end of the antenna  432  may correspond to an upper portion of the plasma chamber  410 . When viewed from the front cross section of the plasma chamber  410 , a height of an opposite end of the antenna  432  may correspond to the lower portion of the plasma chamber  410 . 
     The power source  434  may apply power to the antenna  432 . The power source  434  may apply a high frequency alternating current to the antenna  432 . The high frequency alternating current applied to the antenna  432  may form an inductive electric field in the plasma generating space  412 . The process gas supplied into the plasma generating space  412  may be converted to a plasma state by obtaining an energy required for ionization from the inductive electric field. Also, the power source  434  may also be connected to the one end of the antenna  432 . The power source  434  may be connected to one end of an antenna  432 , a height of the antenna  432  corresponds to the upper portion of the plasma chamber  410 . In addition, an opposite end of the antenna  432  may be grounded. The opposite end of the antenna  432  may be grounded, a height of the antenna  432  corresponds to the lower portion of the plasma chamber  410 . However, the power source  434  may be connected to the opposite end of the antenna  432  and the one end of the antenna  432  may be grounded. 
     The diffusion chamber  440  may diffuse the plasma generated in the plasma chamber  410 . The diffusion chamber  440  may be arranged below the plasma chamber  410 . An upper portion and a lower portion of the diffusion chamber  440  may be opened. The diffusion chamber  440  may be an inverted funnel shape. The upper portion of the diffusion chamber  440  may have a diameter corresponding to the plasma chamber  410 . The lower portion of the diffusion chamber  440  may have a larger diameter than the upper portion of the diffusion chamber  440 . The lower portion diameter of the diffusion chamber  440  may be larger than the upper portion diameter. Also, the diffusion chamber  440  may have a diffusion space  442 . The plasma generated in the plasma generating space  412  may diffuse through the diffusion space  442 . The plasma introduced into the diffusion space  442  may be introduced into the treating space  412  through the baffle  250 . 
     The exhaust unit  600  may exhaust process gases and by-products from the process treating unit  200  to the outside. The exhaust unit  600  may exhaust by-products generated in the process of treating the substrate ‘W’ to the outside of the substrate treating apparatus  1000 . The exhaust unit  600  may exhaust process gases supplied into the treating space  212  to the outside. The exhaust unit  600  may comprise an exhaust line  602  and a decompression member  604 . The exhaust line  602  may be connected to an exhaust hole  214  formed on the bottom surface of the housing  210 . Also, the exhaust line  602  may be connected to a decompression member  604  that provides decompression. Thus, the decompression member  604  may provide decompression to the treating space  212 . The decompression member  604  may be a pump. The decompression member  604  can discharge the plasma and by-products remaining in the treating space  212  to the outside of the housing  210 . In addition, the decompression member  604  may provide a decompression to maintain the pressure of the treating space  212  at a predetermined pressure. 
       FIG. 3  shows a plasma chamber according to an embodiment of the inventive concept. Referring to  FIG. 3 , a first coating film C 1  may be provided on inside walls of the plasma chamber  410 . The first coating film C 1  may cover the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided on the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided with the same thickness on the entire inside walls of the plasma chamber  410 . The first coating film C 1  may comprise yttrium fluoride (YF3). The first coating film C 1  may be coated on the inside walls of the plasma chamber  410  by a method of an atmospheric plasma spray (APS). However, the first coating film C 1  may be coated on the inside walls of the plasma chamber  410  by a method of an aerosol or a cold spray. 
       FIG. 4  shows plasma flow generated from the plasma chamber of  FIG. 3 . Referring to  FIG. 4 , a plasma P may be generated in the plasma generating space  412  of the plasma chamber  410 . Specifically, a process gas may be supplied to the plasma generating space  412 . The process gas supplied to the plasma generating space  412  may be excited with a state of the plasma P by an electric field which the antenna  432  forms. When viewed from a front cross-section of the plasma chamber  410 , the plasma P may move in a lateral direction. In addition, the plasma P may relatively move to the upper area and/or the lower area of the plasma chamber  410 . This is because one end of the antenna  432  is provided with a height corresponding to the upper area of the plasma chamber  410 , and an opposite end of the antenna  432  is provided with a height corresponding to the lower area of the plasma chamber  410 . Specifically, a power source  434  is connected to the one end of the antenna  432 . The opposite end of the antenna  432  is grounded. Thus, the one end of the antenna  432  and/or the opposite end have a greater potential value than the other area of the antenna  432 . Accordingly, the plasma P remaining in the plasma generating space  412  moves in a direction toward the upper and lower areas of the plasma chamber  410  than the central area of the plasma chamber  410 . 
     In the case of an inductively coupled plasma apparatus for generating the plasma P using the antenna  432  wound multiple times on the plasma chamber  410 , the generated plasma P moves in a direction toward the inside walls of the plasma chamber  410 . Accordingly, the plasma chamber  410  is etched by a physical force of the plasma P colliding with the plasma chamber  410 , as well as a chemical reaction with the plasma P. That is, the problem that the chamber is etched by the plasma P occurs more frequently in the inductively coupled plasma apparatus than the capacitively coupled plasma apparatus. Generally, in order to minimize this problem, a method for coating yttrium oxide (Y2O3) on the inside walls of the chamber has been used. However, when a process gas comprising fluorine is applied, yttrium oxide (Y2O3) coating generates particles because the coating film is etched. In other words, the yttrium oxide (Y2O3) coating film has a low ability to suppress the generation of particles. 
     However, according to an embodiment of the inventive concept, the first coating film C 1  comprising yttrium fluoride (YF3) is provided on the inside walls of the plasma chamber  410 . Yttrium fluoride (YF3) has a high ability for suppressing the generation of particles comparing to yttrium oxide (Y2O3). Accordingly, the generation of particles may be minimized in the plasma chamber  410 . The effect of suppressing the generation of particles is greater in the inductively coupled plasma apparatus for the same reasons as described above. 
       FIG. 5  shows a plasma chamber according to another embodiment of the inventive concept. Referring to  FIG. 5 , the first coating film C 1  and a second coating film C 2  may be provided on inside walls of the plasma chamber  410 . The first coating film C 1  and the second coating film C 2  may be formed of different materials, respectively. The first coating film C 1  may cover the inside walls of the plasma chamber  410 . The second coating film C 2  may cover the inside walls of the plasma chamber  410 . A second coating film C 2  may be provided on the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided on the second coating film C 2 . The sum of the thicknesses of the first coating film C 1  and the second coating film C 2  can be the same in the entire area of the inside walls of the plasma chamber  410 . In addition, a bonding ability of the first coating film C 1  and the second coating film C 2  may be larger than that of the first coating film C 1  and the plasma chamber  410 . In addition, the difference between a coefficient of thermal expansion of the second coating film C 2  and that of the plasma chamber  410  may be smaller than the difference between the coefficient of thermal expansion of the second coating film C 2  and that of the first coating film C 1 . The first coating film C 1  may comprise yttrium fluoride (YF3). The second coating layer C 2  may comprise yttrium oxide (Y2O3). The first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an Atmospheric Plasma Spray (APS). However, the first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an aerosol or a cold spray. 
       FIG. 6  shows plasma flow generated from the plasma chamber of  FIG. 5 . Referring to  FIG. 6 , for the same or similar reasons as described above, the plasma P in the plasma generating space  412  can move in a lateral direction. In addition, the plasma P in the plasma generating space  412  can move in a direction toward the upper area and/or the lower area of the plasma chamber  410  when viewed from the front cross section of the plasma chamber  410 . The first coating film C 1  may be provided on the second coating film C 2 . The first coating film C 1  may comprise yttrium fluoride (YF3) having high particle suppression ability. That is, the first coating film C 1  directly collides with the plasma P of the plasma generating space  412 . However, since the first coating film C 1  has a superior particle suppressing ability as described above, the first coating film C 1  may minimize the generation of particles in the plasma generating space  412 . 
     Also, when the first coating film C 1  is provided on the plasma chamber  410 , the first coating film C 1  may be damaged in the process of generating the plasma P, or the first coating film C 1  may be detached from the plasma chamber  410 . For example, when the plasma chamber  410  is provided in a material comprising aluminum oxide (Al2O3) and the first coating film C 1  is provided in a material comprising yttrium fluoride (YF3), the difference between the coefficient of thermal expansion of the first coating film C 1  and the coefficient of thermal expansion of the plasma chamber  410  is large. Heat is generated while generating the plasma P in the plasma generating space  412 . By this heat, the first coating film C 1  and the plasma chamber  410  are thermally deformed. When the difference between the coefficient of thermal expansion of the first coating film C 1  and the plasma chamber  410  is large, the degree of thermal deformation of the first coating film C 1  and the degree of thermal deformation of the plasma chamber  410  are different. Accordingly, the first coating film C 1  may be detached from the plasma chamber  410  by thermal deformation. 
     However, in another embodiment of the inventive concept, the second coating film C 2  is provided on the plasma chamber  410 . In addition, the first coating film C 1  is provided on the second coating film C 2 . Here, the difference between the coefficient of thermal expansion of the second coating film C 2  and the coefficient of thermal expansion of the plasma chamber  410  is smaller than the difference between the coefficient of thermal expansion of the second coating film C 2  and the coefficient of thermal expansion of the first coating film C 1 . For example, when the first coating film C 1  comprises yttrium fluoride (YF3), the second coating film C 2  comprises yttrium oxide (Y2O3), and a material of the plasma chamber  410  comprises aluminum oxide (Al2O3), the difference between the coefficient of thermal expansion of the second coating film C 2  and the coefficient of thermal expansion of the plasma chamber  410  is smaller than the difference between the coefficient of thermal expansion of the second coating film C 2  and the coefficient of thermal expansion of the first coating film C 1 . The coefficient of thermal expansion of the second coating film C 2  may be the same or similar to the coefficient of thermal expansion of the plasma chamber  410 . That is, the degree of thermal deformation of the second coating film C 2  is the same as or similar to the degree of thermal deformation of the plasma chamber  410 . Therefore, detaching the second coating film C 2  from the plasma chamber  410  due to thermal deformation may be minimized. 
     In addition, a bonding ability between the first coating film C 1  and the second coating film C 2  may be larger than that of the first coating film C 1  and the plasma chamber  410 . For example, when the first coating film C 1  comprises yttrium fluoride (YF3), the second coating film C 2  comprises yttrium oxide (Y2O3), and a material of the plasma chamber  410  comprises aluminum oxide (Al2O3), the bonding ability between the first coating film C 1  and the second coating film C 2  may be larger than the bonding ability between the first coating film C 1  and the plasma chamber  410 . Accordingly, even if the degree of thermal deformation of the first coating film C 1  and the second coating film C 2  are different, detaching the first coating film C 1  from the second coating film C 2  may be minimized. 
       FIG. 7  shows a plasma chamber according to another embodiment of the inventive concept. Referring to  FIG. 7 , the first coating film C 1  and the second coating film C 2  may be provided on inside walls of the plasma chamber  410 . The first coating film C 1  may cover the inside walls of the plasma chamber  410 . The second coating film C 2  may cover the inside walls of the plasma chamber  410 . A second coating film C 2  may be provided on the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided on the second coating film C 2 . 
     In addition, when viewed from a front cross-section of the plasma chamber, when it comes to a thickness of the first coating film C 1 , the thickness of an upper area and a lower area of the plasma chamber  410  is thicker than a central area of the plasma chamber  410 . The sum of the thicknesses of the first coating film C 1  and the second coating film C 2  may be the same in the entire area of the inside walls of the plasma chamber  410 . In addition, a bonding ability between the first coating film C 1  and the second coating film C 2  may be larger than that of the first coating film C 1  and the plasma chamber  410 . In addition, the difference between a coefficient of thermal expansion of the second coating film C 2  and that of the plasma chamber  410  may be smaller than the difference between the coefficient of thermal expansion of the second coating film C 2  and that of the first coating film C 1 . The first coating film C 1  may comprise yttrium fluoride (YF3). The second coating layer C 2  may comprise yttrium oxide (Y2O3). The first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an atmospheric plasma spray (APS). However, the first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an aerosol or a cold spray. 
       FIG. 8  shows plasma flow generated from the plasma chamber of  FIG. 7 . Referring to  FIG. 8 , for the same or similar reasons as described above, the plasma P in the plasma generating space  412  can move in a lateral direction. In addition, the plasma P in the plasma generating space  412  can move in a direction toward the upper area and/or the lower area of the plasma chamber  410  when viewed from the front cross-section of the plasma chamber  410 . Accordingly, etching the first coating film C 1  by the plasma P may be performed more in the upper area and the lower area of the plasma chamber  410  than the central area of the plasma chamber  410 . 
     If the thickness of the first coating film C 1  and the second coating film C 2  are the same and the first coating film C 1  provided to the upper area and the lower area of the plasma chamber  410  is etched, the plasma chamber  410  should be replaced or the coating film of the plasma chamber  410  should be re-coated. However, according to another embodiment of the inventive concept, the thickness of the first coating film C 1  provided to the upper and lower areas of the plasma chamber  410  is thick. In other words, by making higher thickness of the first coating film C 1  which has a high ability of suppressing particles in the upper and lower areas of the plasma chamber  410  where frequently collided with the plasma P, a useful life of the plasma chamber  410  may be increased. Other embodiments of the inventive concept described in  FIGS. 7 and 8  are the same as or similar to those of the above-described embodiments, and thus detailed descriptions thereof will be omitted. 
       FIG. 9  shows a plasma chamber according to another embodiment of the inventive concept. Referring to  FIG. 9 , the first coating film C 1  and a second coating film C 2  may be provided on inside walls of the plasma chamber  410 . The first coating film C 1  may cover the inside walls of the plasma chamber  410 . The second coating film C 2  may cover the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided on the inside walls of the plasma chamber  410 . A second coating film C 2  may be provided on the inside walls of the plasma chamber  410 . The first coating film C 1  may be provided with the same thickness on the entire inside walls of the plasma chamber  410 . The second coating film C 2  may be provided with the same thickness on the entire inside walls of the plasma chamber  410 . The thickness of the first coating film C 1  and the second coating film C 2  may be similar. When viewed from a front cross section of the plasma chamber  410 , the first coating film C 1  may be provided to the upper and the lower areas of the plasma chamber  410 . When viewed from the front cross section of the plasma chamber  410 , the second coating film C 2  may be provided to the central area of the plasma chamber  410 . 
     In addition, the difference between a coefficient of thermal expansion of the second coating film C 2  and that of the plasma chamber  410  may be smaller than the difference between the coefficient of thermal expansion of the second coating film C 2  and that of the first coating film C 1 . The first coating film C 1  may comprise yttrium fluoride (YF3). The second coating layer C 2  may comprise yttrium oxide (Y2O3). The first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an Atmospheric Plasma Spray (APS). However, the first coating film C 1  and the second coating film C 2  may be coated on the inside walls of the plasma chamber  410  by the method of an aerosol or a cold spray. 
       FIG. 10  shows plasma flow generated from the plasma chamber of  FIG. 9 . Referring to  FIG. 10 , for the same or similar reasons as described above, the plasma P in the plasma generating space  412  can move in a lateral direction. In addition, the plasma P in the plasma generating space  412  can move in a direction toward the upper area and/or the lower area of the plasma chamber  410  when viewed from the front cross section of the plasma chamber  410 . In addition, a temperature of the plasma generating space  412  may be higher than the upper area and/or the lower area of the plasma chamber  410 . According to another embodiment of the inventive concept, the first coating film C 1  is provided on the upper and lower areas of the plasma chamber  410 . In addition, the second coating film C 2  is provided on a central area of the plasma chamber  410 . That is, since the upper area and/or the lower area of the plasma chamber  410  are in an area where a collision with the plasma P is frequent, the first coating film C 1  may be provided on the upper area and the lower area of the plasma chamber  410 , thereby maximally suppressing the generation of particles. In addition, since the central area of the plasma chamber  410  is the highest temperature area, the second coating film C 2  having a similar thermal expansion coefficient to the plasma chamber  410  is provided on the central area of the plasma chamber  410 . Accordingly, even if the second coating film C 2  is thermally deformed, detaching the second coating film C 2  from the plasma chamber  410  may be minimized. Other effects of other embodiments of the inventive concept described in  FIGS. 9 and 10  are the same as or similar to those of the above-described embodiments, and thus detailed descriptions thereof will be omitted. 
     The embodiments described above can be variously applied to the substrate treating apparatus using the plasma. For example, the embodiments described above may be applied to various apparatuses performing an ashing process, a deposition process, an etching process, or a clean process using the plasma. 
     In addition, in the embodiments described above, the first coating film C 1  comprises yttrium fluoride (YF3), and the second coating film C 2  comprises yttrium oxide (Y2O3), but these are not limited hereto. For example, the first coating film C 1  may comprise any one of yttrium fluoride, yttrium oxide, and yttrium oxyfluoride (YOF), and the second coating film C 2  may comprise any one of yttrium fluoride, yttrium oxide, and yttrium oxyfluoride (YOF). 
     The above description has been made for the illustrative purpose. Furthermore, the above-mentioned contents describe the exemplary embodiment of the inventive concept, and the inventive concept may be used in various other combinations, changes, and environments. That is, the inventive concept can be modified and corrected without departing from the scope of the inventive concept that is disclosed in the specification, the equivalent scope to the written disclosures, and/or the technical or knowledge range of those skilled in the art. The written embodiment describes the best state for implementing the technical spirit of the inventive concept, and various changes required in the detailed application fields and purposes of the inventive concept can be made. Accordingly, the detailed description of the inventive concept is not intended to limit the inventive concept to the disclosed embodiments. Furthermore, it should be construed that the attached claims include other embodiments.