Patent Publication Number: US-10774421-B2

Title: Semiconductor device manufacturing method, substrate processing apparatus and recording medium

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2016-055364, filed on Mar. 18, 2016, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a semiconductor device manufacturing method, a substrate processing apparatus and a non-transitory computer-readable recording medium. 
     BACKGROUND 
     As one of many processes of manufacturing a semiconductor device, a process of loading a substrate into a process chamber of a substrate processing apparatus, supplying a precursor gas and a reaction gas into the process chamber, and forming various kinds of films such as an insulating film, a semiconductor film, a conductor film or the like on the substrate, or a process of removing these films from the substrate, is often carried out. 
     In mass production devices where fine patterns are formed, there is a desire to lower a temperature so as to suppress the diffusion of impurities or allow a material having low heat resistance, such as an organic material or the like, to be used. 
     To cope with this problem, a plasma-based substrate process is generally performed. However, active species such as ions, radicals or the like generated by plasma vary in terms of quantity and lifetime depending on a type, which makes it difficult to uniformly process a film. 
     SUMMARY 
     The present disclosure provides some embodiments of a technique for facilitating a uniform substrate process. 
     According to one embodiment of the present disclosure, there is provided a substrate processing apparatus including: a reaction tube with a process chamber defined therein, the process chamber being configured to process a substrate; a heating device installed outside the reaction tube and configured to heat the process chamber; a gas supply part installed inside the reaction tube and configured to supply a process gas used in processing the substrate; and a plasma generating part including an electrode composed of a first electrode portion connected to a high frequency power supply and a second electrode portion grounded to the earth, which are installed to surround the entire circumference of an outer wall of the reaction tube, wherein an inter-electrode distance between the first electrode portion and the second electrode portion which are adjacent to each other is determined by at least a frequency of the high frequency power supply and a voltage applied across the electrode, and the first electrode portion and the second electrode portion are installed based on the determined inter-electrode distance. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic configuration view of a vertical processing furnace of a substrate processing apparatus suitably used in an embodiment of the present disclosure, in which a portion of the processing furnace is shown in a vertical cross section. 
         FIG. 2  is a partially-enlarged sectional view taken along line A-A in the substrate processing apparatus shown in  FIG. 1 . 
         FIG. 3  is a view for explaining a configuration of a plasma generating part in the substrate processing apparatus shown in  FIG. 1 . 
         FIG. 4  is a schematic configuration view of a controller of the substrate processing apparatus shown in  FIG. 1 , in which one example of a control system of the controller is shown in a block diagram. 
         FIG. 5  is a flowchart showing one example of a substrate processing process using the substrate processing apparatus shown in  FIG. 1 . 
         FIG. 6  is a view showing a first modification of the embodiment of the present disclosure. 
         FIGS. 7A to 7E  are views showing five examples of a second modification of the embodiment of the present disclosure, respectively. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiment of the Present Disclosure 
     An embodiment of the present disclosure will now be described with reference to  FIGS. 1 to 5 . 
     (1) Configuration of Substrate Processing Apparatus 
     (Heating Device) 
     As shown in  FIG. 1 , a processing furnace  202  includes a heater  207  as a heating device (a heating mechanism). The heater  207  has a cylindrical shape and is supported by a heater base (not shown) serving as a support plate so as to be vertically installed. As will be described later, the heater  207  functions as an activation mechanism (an excitation part) configured to thermally activate (excite) a gas. 
     (Process Chamber) 
     An electrode  300  of a plasma generating part to be described later is disposed in the inner side of the heater  207 . In addition, a reaction tube  203  is disposed inside the heater  207  in a concentric relationship with the heater  207 . The reaction tube  203  is made of a heat resistant material such as quartz (SiO 2 ), silicon carbide (SiC), silicon nitride (SiN) or the like and is formed in a cylindrical shape with its upper end closed and its lower end opened. A manifold  209  is disposed in a concentric relationship with the reaction tube  203  under the reaction tube  203 . The manifold  209  is made of, e.g., metal such as stainless steel (SUS) or the like and has a cylindrical shape with upper and lower ends opened. An upper end portion of the manifold  209  engages with a lower end portion of the reaction tube  203  so as to support the reaction tube  203 . An O-ring  220   a  serving as a seal member is installed between the manifold  209  and the reaction tube  203 . As the manifold  209  is supported by the heater base, the reaction tube  203  is vertically installed. A process vessel (reaction vessel) is mainly constituted by the combination of the reaction tube  203  and the manifold  209 . A process chamber  201  is formed in a hollow cylindrical portion of the process vessel. The process chamber  201  is configured to accommodate a plurality of wafers  200  as substrates. Incidentally, the process vessel is not limited to the above-described configuration and only the reaction tube  203  may be sometimes referred to as a process vessel. 
     (Gas Supply Part) 
     Nozzles  249   a  and  249   b  are installed inside the process chamber  201  so as to penetrate through a sidewall of the manifold  209 . Gas supply pipes  232   a  and  232   b  are respectively connected to the nozzles  249   a  and  249   b . In this way, the two nozzles  249   a  and  249   b  and the two gas supply pipes  232   a  and  232   b  are installed in the process vessel such that plural kinds of gases are supplied into the process chamber  201 . In a case where only the reaction tube  203  is used as the process vessel, the nozzles  249   a  and  249   b  may be installed so as to penetrate through a sidewall of the reaction tube  203 . 
     Mass flow controllers (MFCs)  241   a  and  241   b , which are flow rate controllers (flow rate control parts), and valves  243   a  and  243   b , which are opening/closing valves, are installed in the gas supply pipes  232   a  and  232   b  in this order from respective upstream sides, respectively. Gas supply pipes  232   c  and  232   d  for supplying an inert gas are respectively connected to the gas supply pipes  232   a  and  232   b  at the downstream sides of the valves  243   a  and  243   b . MFCs  241   c  and  241   d  and valves  243   c  and  243   d  are installed in the gas supply pipes  232   c  and  232   d  in this order from respective upstream sides, respectively. 
     Each of the nozzles  249   a  and  249   b  is disposed in an annular space (when viewed from top) between the inner wall of the reaction tube  203  and the wafers  200  so as to extend upward along a stack direction of the wafers  200  from a lower portion of the inner wall of the reaction tube  203  to an upper portion thereof. That is to say, the nozzles  249   a  and  249   b  are respectively installed in a perpendicular relationship with the surfaces (flat surfaces) of the wafers  200  at a lateral side of the end portions (peripheral portions) of the wafers  200 , which are loaded into the process chamber  201 . Gas supply holes  250   a  and  250   b  through which a gas is supplied are formed in the side surfaces of the nozzles  249   a  and  249   b , respectively. Each of the gas supply holes  250   a  and  250   b  is opened toward the center of the reaction tube  203  to allow the gas to be supplied toward the wafers  200 . The gas supply holes  250   a  and  250   b  may be formed at multiple locations between the lower portion of the reaction tube  203  and the upper portion thereof. 
     As described above, in this embodiment, a gas is transferred through the nozzles  249   a  and  249   b , which are disposed in the vertically-elongated annular space (when viewed from top), i.e., a cylindrical space, defined by the inner surface of the side wall of the reaction tube  203  and the end portions (peripheral portion portions) of the plurality of wafers  200  arranged in the reaction tube  203 . The gas is initially injected into the reaction tube  203 , near the wafers  200 , through the gas supply holes  250   a  and  250   b  formed respectively in the nozzles  249   a  and  249   b . Accordingly, the gas supplied into the reaction tube  203  mainly flows in the reaction tube  203  in a direction parallel to the surfaces of the wafers  200 , i.e., in a horizontal direction. With this configuration, the gas can be uniformly supplied to the respective wafers  200 , thus improving the uniformity of thickness of a film formed on each of the wafers  200 . The gas flowing on the surfaces of the wafers  200 , i.e., the residual gas remaining after reaction, flows toward an exhaust port, i.e., an exhaust pipe  231  which will be described later. The flow direction of the residual gas is not limited to a vertical direction but may be appropriately varied depending on a position of the exhaust port. 
     A precursor containing a predetermined element, for example, a silane precursor gas which contains silicon (Si) as the predetermined element, is supplied from the gas supply pipe  232   a  into the process chamber  201  via the MFC  241   a , the valve  243   a  and the nozzle  249   a.    
     The silane precursor gas refers to a gaseous silane precursor, for example, a gas obtained by vaporizing a silane precursor which remains in a liquid state under room temperature and atmospheric pressure, or a silane precursor which remains in a gas state under room temperature and atmospheric pressure. When the term “precursor” is used herein, it may refer to “a liquid precursor staying in a liquid state,” “a precursor gas staying in a gaseous state,” or both. 
     An example of the silane precursor gas may include a precursor gas containing Si and an amino group (amine group), i.e., an aminosilane precursor gas. An aminosilane precursor is a silane precursor having an amino group. The aminosilane precursor is also a silane precursor having an alkyl group such as a methyl group, an ethyl group or a butyl group, and a precursor containing at least Si, nitrogen (N) and carbon (C). That is to say, the aminosilane precursor used herein may be referred to as an organic-based precursor or an organic aminosilane precursor. 
     An example of the aminosilane precursor gas may include a bis-tertiary-butylaminosilane (SiH 2 [NH(C 4 H 9 )] 2 , abbreviation: BTBAS) gas. BTBAS may be referred to as a precursor gas containing one Si in one molecule and having a Si—N bond, an N—C bond and no Si—C bond. The BTBAS gas acts as a Si source. 
     In the case of using a liquid precursor such as BTBAS which is in a liquid state under room temperature and atmospheric pressure, the liquid precursor is vaporized by a vaporization system such as a vaporizer or a bubbler and is supplied as a silane precursor gas (a BTBAS gas or the like). 
     A reactant differing in chemical structure from the precursor, for example, an oxygen (O)-containing gas, is supplied from the gas supply pipe  232   b  into the process chamber  201  via the MFC  241   b , the valve  243   b  and the nozzle  249   b.    
     The O-containing gas acts as an oxidizing agent (an oxidizing gas), i.e., an O source. An example of the O-containing gas may include an oxygen (O 2 ) gas, vapor (H 2 O gas) or the like. In the case of using the O 2  gas as the oxidizing agent, for example, this gas is plasma-excited using a plasma source (to be described later) and supplied as a plasma excitation gas (O 2 * gas). 
     An inert gas, for example, a nitrogen (N 2 ) gas, is supplied from the gas supply pipes  232   c  and  232   d  into the process chamber  201  via the MFCs  241   c  and  241   d , the valves  243   c  and  243   d , the gas supply pipes  232   a  and  232   b  and the nozzles  249   a  and  249   b , respectively. 
     A precursor supply system as a first gas supply system is mainly configured by the gas supply pipe  232   a , the MFC  241   a  and the valve  243   a . A reactant supply system as a second gas supply system is mainly configured by the gas supply pipe  232   b , the MFC  241   b  and the valve  243   b . An inert gas supply system is mainly configured by the gas supply pipes  232   c  and  232   d , the MFCs  241   c  and  241   d  and the valves  243   c  and  243   d . The precursor supply system, the reactant supply system and the inert gas supply system are simply referred to as a gas supply system (gas supply part). 
     (Substrate Support) 
     As illustrated in  FIG. 1 , a boat  217  serving as a substrate support is configured to support a plurality of, e.g.,  25  to  200  wafers  200 , in such a state that the wafers  200  are arranged in a horizontal posture and in multiple stages along a vertical direction with the centers of the wafers  200  aligned with one another. That is to say, the boat  217  is configured to arrange the wafers  200  in a spaced-apart relationship. The boat  217  is made of a heat resistant material such as quartz or SiC. Heat insulating plates  218  made of a heat resistant material such as quartz or SiC are installed below the boat  217  in multiple stages. With this configuration, it is hard for heat generated from the heater  207  to be radiated to a seal cap  219 . However, this embodiment is not limited to such a configuration. For example, instead of installing the heat insulating plates  218  below the boat  207 , a heat insulating tube as a tubular member made of a heat resistant material such as quartz or SiC may be installed. 
     (Plasma Generating Part) 
     Next, a plasma generating part will be described with reference to  FIGS. 1 to 3 . 
     As illustrated in  FIG. 2 , plasma is generated inside the reaction tube  203 , which is a vacuum partition wall made of quartz or the like, at the time of supplying a reaction gas, by using a capacitively-coupled plasma (CCP). 
     As shown in  FIG. 2 , the electrode  300  is disposed between the reaction tube  203  and the heater  207  so as to surround the entire circumference of the reaction tube  203 . A high frequency wave having a frequency of, e.g., 13.56 MHz is input to the electrode  300  from a high frequency power supply  310  via a matching device  303 . The electrode  300  is mainly composed of a first electrode portion  301  connected to the high frequency power supply  310  and a second electrode portion  302  that is grounded to the earth. An electric field  304  is established between the first electrode portion  301  and the second electrode portion  302  which are adjacent to each other so that plasma is generated inside the reaction tube  203 . Here, as shown in  FIG. 2 , the electric field  304  includes a minimum electric field  304 - 1  formed according to an inter-electrode distance D which will be described later, and a maximum electric field  304 - 2  formed according to an electrode pitch (a distance between the centers of the first electrode  301  and the second electrode  302 ) which will be described later. In other words, the minimum electric field  304 - 1  is formed due to an influence by the inter-electrode distance D and the maximum electric field  304 - 2  is formed due to an influence by the electrode pitch. As shown in  FIG. 3 , the first electrode portion  301  and the second electrode portion  302  are alternately extended in parallel to each other in the same direction as the extension direction of the gas nozzles  249   a  and  249   b . By configuring and disposing the electrode  300  in this manner, it becomes possible to uniformly generate plasma over the entire area within the reaction tube  203  and supply active species for substrate process from the entire circumference of the wafers  200  by means of the uniformly-generated plasma. A plasma generating part is mainly constituted by the electrode  300  (the first electrode portion  301  and the second electrode portion  302 ), the matching device  303  and the high frequency power source  310 . 
     Here, as shown in  FIG. 3 , the inter-electrode distance D between the first electrode portion  301  and the second electrode portion  302  needs be set in such a manner that electrons applied by the high frequency power source  310  make a reciprocating motion without colliding with the first electrode portion  301  and the second electrode portion  302 . Therefore, the inter-electrode distance D can be determined by the following equation (1) according to the energy conservation law and the simple harmonic motion formula. By setting the inter-electrode distance D at a value determined by the equation (1) or its surrounding values (values in a range of half to twice the determined value), it is possible to improve plasma generation efficiency. If the inter-electrode distance D is set to be smaller than half the determined value, electron disappearance on the electrode side becomes remarkable, which allows the plasma to be deactivated easily. In addition, if the inter-electrode distance D is set to be larger than twice the determined value, an electrical action on the electrons becomes remarkably weak, which results in low plasma generation efficiency. 
     
       
         
           
             
               
                 
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     In the above equation [1], V is an inter-electrode voltage, f is a frequency of the high frequency power supply, m is a mass of the electron, and e/m is a specific charge of electrons. 
     For example, when the frequency of the high frequency power supply is set to fall within a range of 2 to 60 MHz and the inter-electrode voltage is set to fall within a range of 25 to 1,000V, the inter-electrode D may be determined to fall within a range of about 0.5 to 94 mm. 
     The electrode  300  can be made of metal such as aluminum, copper, stainless steel or the like but may be made of an oxidation resistant material such as nickel so as to facilitate the substrate process while suppressing deterioration of the electric conductivity of the surface of the electrode. By suppressing the deterioration of the electric conductivity of the surface of the electrode, it is possible to suppress deterioration of the plasma generation efficiency. 
     In a vertical type substrate processing apparatus, plasma of a CCP mode was generated when the temperature of a reaction chamber was set to 500 degrees C., the pressure of the reaction chamber was set to 100 Pa, the frequency of a high frequency power supply was set to 13.56 MHz, and a plurality of high frequency electrodes each having a length of 1 m and an electrode width of 15 mm was arranged at an inter-electrode distance D of 10 mm such that polarities thereof alternate in the outer wall of a tubular reaction tube. In addition, a gap between the inner wall of the reaction tube and a wafer was set to 50 mm in a concentric circle. 
     Here, an internal pressure of a furnace at the time of the substrate process may be controlled to fall within a range of 10 to 300 Pa. The reason for this is as follows. If the internal pressure of the furnace is less than 10 Pa, the mean free path of gas molecules becomes longer than the Debye length of plasma, plasma directly striking a wall of the furnace becomes conspicuous. This makes it difficult to suppress generation of particles. In addition, if the internal pressure of the furnace is more than 300 Pa, the plasma generation efficiency is saturated. Therefore, even if a reaction gas is supplied, the amount of generation of plasma does not change, wastefully consuming the reaction gas. 
     In addition, in this embodiment, the electrode pitch may be set to be twice or more the thickness t of the reaction tube and not more than twice a distance between the peripheral portion of the wafer and the outer wall of the reaction tube. Specifically, the electrode may be formed with the electrode pitch set to fall with a range of 10 to 110 mm. The reason for this is as follows. If the electrode pitch is set to be smaller than twice the thickness t of the reaction tube as shown in  FIG. 2 , all of the electric fields  304  generated by applying a high frequency voltage between the electrodes become shorter than the thickness of the reaction tube in the radial direction of the reaction tube. That is to say, this is because no electric field  304  is formed inside the reaction tube and the generated plasma is prone to be creeping-discharged on the surface of the reaction tube, thereby decreasing the plasma generation efficiency. Further, if the electrode pitch is set to be greater than twice the distance between the peripheral portion of the wafer and the outer wall of the reaction tube, the electric field  304  becomes longer in the radial direction of the reaction tube and reaches the peripheral portion of the wafer, which makes it easier to generate plasma between the electrode and the peripheral portion of the wafer. Upon generating plasma between the electrode and the peripheral portion of the wafer, plasma damage occurs in the wafer, thereby deteriorating the quality of the film. 
     There is a need to set the frequency of the high frequency power supply to a frequency at which electrons reciprocating in plasma have a vibration amplitude capable of vibrating without colliding with the first electrode portion  301  and the second electrode portion  302 . The minimum vibration frequency f 0  at which electrons can vibrate without colliding with the electrodes may be expressed by the following equation (2) according to the energy conservation law and the simple harmonic motion formula. The maximum value X of the vibration amplitude corresponds to half of an electric force line of the high frequency voltage V connecting the centers of the electrodes, and e/m is a specific charge of electrons as in the equation (1). If the frequency of the high frequency power supply is equal to or more than the minimum vibration frequency f 0 , electrons can be secured so that they are not lost at the electrode side, which improves the plasma generation efficiency. 
     
       
         
           
             
               
                 
                   
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     The electric field generated by the inter-electrode voltage may be weakened by the effect of a dielectric, plasma shielding, or the like. As such, a voltage in the inner side of the dielectric and plasma shielding may be lowered. Therefore, in consideration of relative permittivity εr of the reaction tube and Debye shielding of plasma, the equations (1) and (2) are required to be corrected with respect to the inter-electrode voltage V. 
     
       
         
           
             
               
                 
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     In the above equation (3), t is the thickness of the reaction tube and exp(1) is the Napier number (the base of natural logarithm). In this embodiment to be described later, the minimum vibration frequency f 0  is 4.5 MHz when the maximum voltage V is equal to 1,000V. For example, since the above-described high frequency power supply frequency of 13.56 MHz is more than the minimum vibration frequency f 0 , plasma can be generated with high efficiency. 
     By determining the inter-electrode distance D according to the equations (1), (2) and (3) in this way, it is possible to improve the plasma generation efficiency and improve a wafer process speed while improving the uniformity of wafer process. 
     (Exhaust Part) 
     As shown in  FIG. 1 , the exhaust pipe  231  for exhausting an internal atmosphere of the process chamber  201  is installed in the reaction tube  203 . A vacuum pump  246  used as a vacuum exhaust device is connected to the exhaust pipe  231  via a pressure sensor  245 , which is a pressure detector (pressure detecting part) for detecting an internal pressure of the process chamber  201 , and an auto pressure controller (APC) valve  244 , which is an exhaust valve (pressure regulating part). The APC valve  244  is a valve configured to evacuate the interior of the process chamber  201  or stop such an evacuation operation by opening or closing the valve while the vacuum pump  246  is actuated. Further, the APC valve  244  is a valve configured to regulate the internal pressure of the process chamber  201  by adjusting an opening degree of the valve based on pressure information detected by the pressure sensor  245  while the vacuum pump  246  is actuated. An exhaust system is mainly configured by the exhaust pipe  231 , the APC valve  244  and the pressure sensor  245 . The vacuum pump  246  may be regarded as being included in the exhaust system. The exhaust pipe  231  is not limited to being installed in the reaction tube  203  but may be installed in the manifold  209  in the same manner as the nozzles  249   a  and  249   b.    
     (Peripheral Devices) 
     The seal cap  219 , which serves as a furnace opening cover configured to air-tightly seal a lower end opening of the reaction tube  203 , is installed under the manifold  209 . The seal cap  219  is configured to make contact with the lower end of the manifold  209  at a lower side in the vertical direction. The seal cap  219  is made of metal such as, e.g., stainless steel (SUS) or the like, and is formed in a disc shape. An O-ring  220   b , which is a seal member making contact with the lower end of the manifold  209 , is installed on an upper surface of the seal cap  219 . 
     A rotation mechanism  267  configured to rotate the boat  217  is installed at the opposite side of the seal cap  219  from the process chamber  201 . A rotary shaft  255  of the rotation mechanism  267 , which penetrates through the seal cap  219 , is connected to the boat  217 . The rotation mechanism  267  is configured to rotate the wafers  200  by rotating the boat  217 . The seal cap  219  is configured to be vertically moved up and down by a boat elevator  115  which is an elevator mechanism vertically installed outside the reaction tube  203 . The boat elevator  115  is configured to load and unload the boat  217  into and from the process chamber  201  by moving the seal cap  219  up and down. 
     The boat elevator  115  is configured as a transfer device (transfer mechanism) which transfers the boat  217 , i.e., the wafers  200 , into and out of the process chamber  201 . In addition, a shutter  219   s , which serves as a furnace opening cover configured to air-tightly seal the lower end opening of the manifold  209  while the seal cap  219  is descended by the boat elevator  115 , is installed under the manifold  209 . The shutter  219   s  is made of metal such as, e.g., stainless steel (SUS) or the like, and is formed in a disc shape. An O-ring  220   c , which is a seal member making contact with the lower end of the manifold  209 , is installed on an upper surface of the shutter  219   s . The opening/closing operation (such as elevation operation, rotation operation or the like) of the shutter  219   s  is controlled by a shutter opening/closing mechanism  115   s.    
     A temperature sensor  263  serving as a temperature detector is installed inside the reaction tube  203 . Based on temperature information detected by the temperature sensor  263 , a state of supplying electric power to the heater  207  is adjusted such that the interior of the process chamber  201  has a desired temperature distribution. Similar to the nozzles  249   a  and  249   b , the temperature sensor  263  is installed along the inner wall of the reaction tube  203 . 
     (Control Device) 
     Next, a control device will be described with reference to  FIG. 4 .  FIG. 4  is a block diagram showing one example of a controller of the substrate processing apparatus shown in  FIG. 1 . As illustrated in  FIG. 4 , a controller  121 , which is a control part (control device), may be configured as a computer including a central processing unit (CPU)  121   a , a random access memory (RAM)  121   b , a memory device  121   c  and an I/O port  121   d . The RAM  121   b , the memory device  121   c  and the I/O port  121   d  are configured to exchange data with the CPU  121   a  via an internal bus  121   e . An input/output device  122  constituted by, e.g., a touch panel or the like, is connected to the controller  121 . 
     The memory device  121   c  is configured with, e.g., a flash memory, a hard disc drive (HDD) or the like. A control program for controlling operations of a substrate processing apparatus and a process recipe in which sequences and conditions of a film forming process to be described later are written, are readably stored in the memory device  121   c . The process recipe function as a program for causing the controller  121  to execute each sequence in the film forming process (to be described later) to obtain a predetermined result. Hereinafter, the process recipe and the control program will be generally and simply referred to as a “program.” Furthermore, the process recipe will be simply referred to as a “recipe.” When the term “program” is used herein, it may indicate a case of including only the recipe, a case of including only the control program, or a case of including both the recipe and the control program. The RAM  121   b  is configured as a memory area (work area) in which a program or data read by the CPU  121   a  is temporarily stored. 
     The I/O port  121   d  is connected to the MFCs  241   a  to  241   d , the valves  243   a  to  243   d , the pressure sensor  245 , the APC valve  244 , the vacuum pump  246 , the heater  207 , the temperature sensor  263 , the rotation mechanism  267 , the boat elevator  115 , the shutter opening/closing mechanism  115   s , the high frequency power supply  310  and the like. 
     The CPU  121   a  is configured to read and execute the control program from the memory device  121   c . The CPU  121   a  is also configured to read the recipe from the memory device  121   c  according to an input of an operation command from the input/output device  122 . In addition, the CPU  121   a  is configured to control the rotational operation of the rotation mechanism  267 , the flow rate adjusting operation of various kinds of gases by the MFCs  241   a  to  241   d , the opening/closing operation of the valves  243   a  to  243   d , the opening/closing operation of the APC valve  244 , the pressure regulating operation performed by the APC valve  244  based on the pressure sensor  245 , the driving and stopping of the vacuum pump  246 , the temperature adjusting operation performed by the heater  207  based on the temperature sensor  263 , the operation of forward/backward rotation and adjustment operation of rotation angle and rotation speed of the boat  217  with the rotation mechanism  267 , the operation of moving the boat  217  up and down with the boat elevator  115 , the opening/closing operation of the shutter  219   s  with the shutter opening/closing mechanism  115   s , the operation of supply of power of the high frequency power supply  310 , and the like, according to contents of the read recipe. 
     The controller  121  may be configured by installing, on the computer, the aforementioned program stored in an external memory device  123  (for example, a magnetic disc such as a hard disc, an optical disc such as a CD, a magneto-optical disc such as an MO, a semiconductor memory such as a USB memory, etc.). The memory device  121   c  or the external memory device  123  is configured as a non-transitory computer-readable recording medium. Hereinafter, the memory device  121   c  and the external memory device  123  will be generally and simply referred to as a “recording medium.” When the term “recording medium” is used herein, it may indicate a case of including only the memory device  121   c , a case of including only the external memory device  123 , or a case of including both the memory device  121   c  and the external memory device  123 . Furthermore, the program may be supplied to the computer using communication means such as the Internet or a dedicated line, instead of using the external memory device  123 . 
     (2) Substrate Processing Process 
     A process example of forming a film on a substrate using the aforementioned substrate processing apparatus, which is one of many processes for manufacturing a semiconductor device, will be described below with reference to  FIG. 5 . In the following descriptions, the operations of the respective parts constituting the substrate processing apparatus are controlled by the controller  121 . 
     In the present disclosure, for the sake of convenience, a film forming sequence illustrated in  FIG. 5  may sometimes be denoted as follows. The same denotation will be used in modifications and other embodiments to be described later.
 
(BTBAS→O 2 *)× n   SiO
 
     When the term “wafer” is used in the present disclosure, it may refer to “a wafer itself” or “a wafer and a laminated body (aggregate) of predetermined layers or films formed on a surface of the wafer.” That is to say, a wafer including predetermined layers or films formed on its surface may be referred to as a wafer. In addition, when the phrase “a surface of a wafer” is used in the present disclosure, it may refer to “a surface (exposed surface) of a wafer itself” or “a surface of a predetermined layer or film formed on a wafer, namely, an uppermost surface of the wafer, which is a laminated body.” 
     Accordingly, in the present disclosure, the expression “a predetermined gas is supplied to a wafer” may mean that “a predetermined gas is directly supplied to a surface (exposed surface) of a wafer itself” or that “a predetermined gas is supplied to a layer or film formed on a wafer, namely, to an uppermost surface of a wafer as a laminated body.” Furthermore, in the present disclosure, the expression “a predetermined layer (or film) is formed on a wafer” may mean that “a predetermined layer (or film) is directly formed on a surface (exposed surface) of a wafer itself” or that “a predetermined layer (or film) is formed on a layer or film formed on a wafer, namely, to an uppermost surface of a wafer as a laminated body.” 
     In addition, when the term “substrate” is used in the present disclosure, it may be synonymous with the term “wafer.” 
     (Loading Step: S 1 ) 
     Upon a plurality of wafers  200  is charged in the boat  217  (wafer charging), the shutter  219   s  is moved by the shutter opening/closing mechanism  115   s  so that the lower end opening of the manifold  209  is opened (shutter opening). Thereafter, as illustrated in  FIG. 1 , the boat  217  supporting the plurality of wafers  200  is lifted up by the boat elevator  115  to be loaded into the process chamber  201  (boat loading). In this state, the seal cap  219  seals the lower end of the manifold  209  through the O-ring  220   b.    
     (Pressure and Temperature Adjusting Step: S 2 ) 
     The interior of the process chamber  201 , namely the space in which the wafers  200  exist, is vacuum-exhausted (depressurization-exhausted) by the vacuum pump  246  so as to reach a desired pressure (degree of vacuum). In this operation, the internal pressure of the process chamber  201  is measured by the pressure sensor  245 . The APC valve  244  is feedback-controlled based on the measured pressure information. The vacuum pump  246  is continuously activated at least until a film forming step to be described later is completed. 
     The wafers  200  in the process chamber  201  are heated by the heater  207  to a desired temperature. In this operation, the state of supplying electric power to the heater  207  is feedback-controlled based on the temperature information detected by the temperature sensor  263  such that the interior of the process chamber  201  has a desired temperature distribution. The heating of the interior of the process chamber  201  by the heater  207  is continuously performed at least until the film forming step to be described later is completed. However, when the film forming step is performed under a temperature condition of room temperature or lower, the heating of the interior of the process chamber  201  by the heater  207  may be omitted. When a process is merely performed under such a temperature condition, the heater  207  is unnecessary and the heater  207  may not be installed in the substrate processing apparatus. In this case, the configuration of the substrate processing apparatus can be simplified. 
     Subsequently, the rotation of the boat  217  and the wafers  200  by the rotation mechanism  267  begins. The rotation of the boat  217  and the wafers  200  by the rotation mechanism  267  is continuously performed at least until the film forming step to be described later is completed. 
     (Film Forming Steps: S 3 , S 4 , S 5  and S 6 ) 
     Thereafter, steps S 3 , S 4 , S 5  and S 6  are sequentially performed to form a film. 
     (Precursor Gas Supplying Step: S 3  and S 4 ) 
     In Step S 3 , a BTBAS gas is supplied to the wafers  200  in the process chamber  201 . 
     The valve  243   a  is opened to allow the BTBAS gas to flow through the gas supply pipe  232   a . The BTBAS gas, a flow rate of which is adjusted by the MFC  241   a , is supplied from the gas supply holes  250   a  into the process chamber  201  via the nozzle  249   a  and subsequently, is exhausted through the exhaust pipe  231 . At this time, the BTBAS gas is supplied to the wafers  200 . At the same time, the valve  243   c  is opened to allow a N 2  gas to flow through the gas supply pipe  232   c . The N 2  gas, a flow rate of which is adjusted by the MFC  241   c , is supplied into the process chamber  201  together with the BTBAS gas and subsequently, is exhausted through the exhaust pipe  231 . 
     In addition, in order to prevent the BTBAS gas from infiltrating into the nozzle  249   b , the valves  243   d  is opened to allow the N 2  gas to flow through the gas supply pipe  232   d . The N 2  gas is supplied into the process chamber  201  through the gas supply pipe  232   b  and the nozzle  249   b  and subsequently, is exhausted through the exhaust pipe  231 . 
     The supply flow rate of the BTBAS gas, which is controlled by the MFC  241   a , is set to fall within a range of, e.g., 1 to 2,000 sccm, specifically, 10 to 1,000 sccm. The supply flow rates of the N 2  gas, which are respectively controlled by the MFCs  241   c  and  241   d , are set to fall within a range of, e.g., 100 to 10,000 sccm. The internal pressure of the process chamber  201  is set to fall within a range of, e.g., 1 to 2,666 Pa, specifically 67 to 1,333 Pa, as described above. A time period during which the BTBAS gas is supplied to the wafers  200  is set to fall within a range of, e.g., 1 to 100 seconds, specifically, 1 to 50 seconds. 
     The temperature of the heater  207  is set such that the temperature of the wafers  200  falls within a range of, e.g., 0 to 150 degrees C., specifically room temperature (25 degrees C.) to 100 degrees C., more specifically 40 to 90 degrees C. The BTBAS gas is a high-reaction gas which is easily adsorbed onto the wafers  200  or the like. Therefore, even when the temperature is as low as, for example, room temperature, the BTBAS gas can be chemisorbed onto the wafers  200 , which makes it possible to obtain a practical deposition rate. By setting the temperature of the wafers  200  to 150 degrees C. or lower, further 100 degrees C. or lower, ultimately 90 degrees C. or lower as in the present embodiment, the amount of heat applied to the wafers  200  can be reduced and the thermal history undertaken by the wafers  200  can be satisfactorily controlled. In addition, at a temperature of 0 degrees C. or higher, the BTBAS gas can be sufficiently adsorbed onto the wafers  200 , which makes it possible to obtain a sufficient deposition rate. Therefore, the temperature of the wafers  200  may be set to fall within the range of 0 to 150 degrees C., specifically room temperature to 100 degrees C., more specifically 40 to 90 degrees C. 
     By supplying the BTBAS gas to the wafers  200  under the aforementioned conditions, a Si-containing layer having a thickness of from less than one atomic layer (one molecular layer) to several atomic layers (several molecular layers) is formed on each of the wafers  200  (underlying films of the surfaces thereof). The Si-containing layer may be a Si layer, an adsorption layer of BTBAS, or both. 
     The Si layer is a generic name that encompasses a continuous or discontinuous layer composed of Si and a Si thin film formed of the layers overlapping with one another. The Si which constitutes the Si layer includes not only Si whose bond to an amino group is not completely broken but also Si whose bond to H is completely broken. 
     The adsorption layer of BTBAS includes not only a continuous adsorption layer composed of BTBAS molecules but also a discontinuous adsorption layer. The BTBAS molecules that constitute the adsorption layer of BTBAS include molecules whose bond to Si and an amino group is partially broken, whose bond to Si and H is partially broken, or whose bond to N and C is partially broken. That is to say, the adsorption layer of BTBAS may be a physical adsorption layer of BTBAS, a chemisorption layer of BTBAS, or both. 
     In this regard, the layer having a thickness of less than one atomic layer (one molecular layer) may mean an atomic layer (a molecular layer) that is discontinuously formed. The layer having a thickness of one atomic layer (one molecular layer) may mean an atomic layer (a molecular layer) that is continuously formed. The Si-containing layer may include both a Si layer and an adsorption layer of BTBAS. However, as described above, expressions such as “one atomic layer”, “several atomic layers” and the like will be used with respect to the Si-containing layer, and the term “atomic layer” may be synonymous with the term “molecular layer.” 
     Under a condition in which the BTBAS gas is autolyzed (or pyrolyzed), i.e., a condition in which a pyrolysis reaction of the BTBAS gas is generated, Si is deposited on the wafer  200  to form a Si layer. Under a condition in which the BTBAS gas is not autolyzed (or pyrolyzed), i.e., a condition in which a pyrolysis reaction of the BTBAS gas is not generated, BTBAS is adsorbed onto the wafer  200  to form an adsorption layer of BTBAS. However, in the present embodiment, since the temperature of the wafer  200  is set to a low temperature of, for example, 150 degrees C. or less, the pyrolysis of BTBAS hardly occurs. As a result, the adsorption layer of BTBAS rather than the Si layer is more likely to be formed on the wafer  200 . 
     If the thickness of the Si-containing layer formed on the wafer  200  exceeds several atomic layers, a modification action in a modifying step (to be described later) does not reach the entire Si-containing layer. In addition, a possible minimum value of the thickness of the Si-containing layer formed on the wafer  200  is less than one atomic layer. Accordingly, the thickness of the Si-containing layer may be set to fall within a range of less than one atomic layer to several atomic layers. By setting the thickness of the Si-containing layer to one atomic layer or less, namely one atomic layer or less than one atomic layer, it is possible to relatively increase the modification action in the modifying step which will be described later and to shorten the time required for a modifying reaction in the modifying step. It is also possible to shorten the time required for formation of the Si-containing layer in the film forming step. As a result, it is possible to shorten the process time per one cycle and hence shorten the total process time. That is to say, it is possible to increase the deposition rate. Furthermore, by setting the thickness of the Si-containing layer to one atomic layer or less, it is possible to enhance the controllability of the film thickness uniformity. 
     After the Si-containing layer is formed, the valve  243   a  is closed to stop the supply of the BTBAS gas into the process chamber  201 . At this time, the interior of the process chamber  201  is vacuum-exhausted by the vacuum pump  246  with the APC valve  244  left opened. Thus, the unreacted BTBAS gas remaining in the process chamber  201 , or the BTBAS gas which remains after contributing to the formation of the Si-containing layer, byproducts or the like, are discharged from the interior of the process chamber  201 . In addition, with the valves  243   c  and  243   d  left opened, the supply of the N 2  gas into the process chamber  201  is maintained. The N 2  gas acts as a purge gas. This step S 4  may be omitted and a precursor gas supplying step may be used instead. 
     As the precursor gas, in addition to the BTBAS gas, it may be possible to suitably use a tetrakisdimethylaminosilane (Si[N(CH 3 ) 2 ] 4 , abbreviation: 4DMAS) gas, a trisdimethylaminosilane (Si[N(CH 3 ) 2 ] 3 H, abbreviation: 3DMAS) gas, a bisdimethylaminosilane (Si[N(CH 3 ) 2 ] 2 H 2 , abbreviation: BDMAS) gas, a bisdiethylaminosilane (Si[N(C 2 H 5 ) 2 ] 2 H 2 , abbreviation: BDEAS) gas or the like. Besides, as the precursor gas, it may be possible to suitably use various kinds of anminosilane precursor gases such as a dimethylaminosilane (DMAS) gas, a diethylaminosilane (DEAS) gas, a dipropylaminosilane (DPAS) gas, a diisopropylaminosilane (DIPAS) gas, a butylaminosilane (BAS) gas, a hexamethyldisilazane (HMDS) gas and the like; an inorganic halosilane precursor gas such as a monochlorosilane (SiH 3 Cl, abbreviation: MCS) gas, a dichlorosilane (SiH 2 Cl 2 , abbreviation: DCS) gas, a trichlorosilane (SiHCl 3 , abbreviation: TCS) gas, a tetrachlorosilane, i.e., silicon tetrachloride (SiCl 4 , abbreviation: STC) gas, a hexachlorodisilane (Si 2 Cl 6 , abbreviation: HCDS) gas, an octachlorotrisilane (Si 3 Cl 8 , abbreviation: OCTS) gas or the like; and an inorganic silane precursor gas containing no halogen group such as a monosilane (SiH 4 , abbreviation: MS) gas, a disilane (Si 2 H 6 , abbreviation: DS) gas, a trisilane (Si 3 H 8 , abbreviation: TS) gas or the like. 
     As the inert gas, in addition to the N 2  gas, a rare gas such as an Ar gas, He gas, Ne gas, Xe gas or the like may be used. 
     (Reaction Gas Supplying Step: S 5  and S 6 ) 
     After the film forming process is completed, a plasma-excited O 2  gas as a reaction gas is supplied to the wafers  200  in the process chamber  201  (S 5 ). 
     In this step, the opening/closing control of the valves  243   b  to  243   d  is performed in the same procedure as the opening/closing control of the valves  243   a ,  243   c  and  243   d  in the step S 3 . The O 2  gas, a flow rate of which is adjusted by the MFC  241   b , is supplied into the process chamber  201  from the gas supply holes  250   b  via the nozzle  249   b . At this time, high frequency power (having a frequency of 13.56 MHz, in the present embodiment) is supplied (applied) from the high frequency power supply  310  to the electrode  300 . The O 2  gas supplied into the process chamber  201  is excited into a plasma state inside the process chamber  201 , and is supplied. Gas thus plasma-excited is supplied as active species (O 2 *) with respect to the wafers  200  via the gas supply holes  250   c , and subsequently, is exhausted through the exhaust pipe  231 . The plasma-excited O 2  gas is also referred to as oxygen plasma. 
     The supply flow rate of the O 2  gas controlled by the MFC  241   b  is set to fall within a range of, for example, 100 to 10,000 sccm. The high frequency power applied from the high frequency power supply  310  to the electrode  300  is set to fall within a range of, e.g., 50 to 1,000 W. The internal pressure of the process chamber  201  is set to fall within a range of, e.g., 10 to 300 Pa. By using plasma, it is possible to activate the O 2  gas even if the internal pressure of the process chamber  201  is set at such a relatively low pressure band. A time period during which the active species obtained by plasma-exciting the O 2  gas are supplied to the wafer  200  is set to fall within a range of, e.g., 1 to 100 seconds, specifically 1 to 50 seconds. Other process conditions are the same as those in the aforementioned step S 3 . 
     Ions generated in the oxygen plasma and the electrically-neutral active species are used in performing an oxidation process (to be described later) on the Si-containing layer formed on the surface of the wafer  200 . 
     By supplying the O 2  gas to the wafer  200  under the aforementioned conditions, the Si-containing layer formed on the wafer  200  is plasma-oxidized. At this time, Si—N bonds and Si—H bonds contained in the Si-containing layer are cleaved by the energy of the plasma-excited O 2  gas. N and H separated from bonds with Si, and C bonding to N, are separated from the Si-containing layer. Then, Si in the Si-containing layer, which has a dangling bond as N or the like is separated, combines with O contained in the O 2  gas to form a Si—O bond. As this reaction proceeds, the Si-containing layer is changed (modified) into a layer containing Si and O, namely a silicon oxide layer (SiO layer). 
     To modify the Si-containing layer into the SiO layer requires plasma-exciting the O 2  gas to be supplied. The reason for this is as follows. Even if the O 2  gas is supplied under a non-plasma atmosphere, the energy necessary to oxidize the Si-containing layer is insufficient in the aforementioned temperature band. As such, it is difficult to sufficiently separate N or C from the Si-containing layer. Further, it is difficult to sufficiently oxidize the Si-containing layer, which fails to increase the Si—O bond. 
     After the Si-containing layer is changed into the SiO layer, the valve  243   b  is closed to stop the supply of the O 2  gas. In addition, the supply of the high frequency power to the electrode  300  is stopped. Then, according to the same process procedure and process conditions as in the step S 4 , the O 2  gas or the byproducts, which remains in the process chamber  201 , is eliminated from the interior of the process chamber  201  (step S 6 ). Alternatively, this step S 6  may be omitted and the reaction gas supplying step may be used instead. 
     As the oxidizing agent, i.e., the O-containing gas to be plasma-excited, in addition to the O 2  gas, a nitrous oxide (N 2 O) gas, a nitric oxide (NO) gas, a nitrogen dioxide (NO 2 ) gas, an ozone (O 3 ) gas, a hydrogen peroxide (H 2 O 2 ) gas, vapor (H 2 O gas), a carbon monoxide (CO) gas, a carbon dioxide (CO 2 ) gas or the like may be used. 
     As the inert gas, in addition to the N 2  gas, various rare gases exemplified in the step S 4  may be used. 
     (Performing Cycle a Predetermined Number of Times: S 7 ) 
     By performing one cycle in which the aforementioned steps S 3 , S 4 , S 5  and S 6  are performed in this order in a non-simultaneous or asynchronous manner a predetermined number of times (n times), i.e., once or more, it is possible to form a SiO film having a predetermined composition and a predetermined film thickness on the wafer  200 . The above cycle may be repeated a plurality of times. That is to say, the thickness of the SiO layer formed per cycle may be made smaller than a desired film thickness, and the above cycle may be repeated the plurality of times until the film thickness of the SiO film formed by laminating SiO layers reaches the desired film thickness. 
     (Atmospheric Pressure Returning Step: S 8 ) 
     After the aforementioned film forming process is completed, the N 2  gas as the inert gas is supplied into the process chamber  201  from each of the gas supply pipes  232   c  and  232   d  and subsequently, is exhausted through the exhaust pipe  231 . Thus, the interior of the process chamber  201  is purged with the inert gas and therefore the residual O 2  gas and the like remaining in the process chamber  201  are removed from the interior of the process chamber  201  (inert gas-based purging). Thereafter, the internal atmosphere of the process chamber  201  is substituted with the inert gas (inert gas substituting), and the internal pressure of the process chamber  201  is returned to the atmospheric pressure (atmospheric pressure returning: S 8 ). 
     (Unloading Step: S 9 ) 
     Thereafter, the seal cap  219  is moved down by the boat elevator  115  so that the lower end of the manifold  209  is opened, and the processed wafers  200  supported by the boat  217  are unloaded from the lower end of the manifold  209  outside of the reaction tube  203  (boat unloading). After the boat unloading, the shutter  219   s  is moved and the lower end opening of the manifold  209  is sealed by the shutter  219   s  via the O-ring  220   c  (shutter closing). The processed wafers  200  are unloaded from the reaction tube  203  and are discharged from the boat  217  (wafer discharging). Subsequently, after the wafer discharging, the empty boat  217  may be loaded into the process chamber  201 . 
     (3) Effects According to the Present Embodiment 
     According to the present embodiment, one or more effects set forth below may be achieved. 
     (a) By placing an electrode over the entire circumference of a reaction tube, it is possible to uniformly supply active species from the entire circumference of a wafer. It is therefore possible to increase an amount of the active species reaching the wafer, thus improving a process speed of a wafer process while improving the uniformity of the wafer process. 
     (b) By setting an inter-electrode distance at a constant value determined by a predetermined equation, it is possible to improve plasma generation efficiency. In addition, since the plasma generation efficiency is improved, it is possible to improve the process speed of the wafer process while improving the uniformity of the wafer process. 
     (c) there is no need to change an internal structure of the reaction tube by disposing the electrode outside a process chamber. This suppresses the generation of particles and contamination caused by metal in the process chamber. 
     (d) By making the electrode of an oxidation resistant material, it is possible to reduce oxidation in a surface of the electrode, thus suppressing degradation of electric conductivity. 
     (4) Modifications 
     The substrate processing process in the present embodiment is not limited to the aforementioned aspects but may be changed as in the following modifications. 
     First Modification 
     As illustrated in  FIG. 6 , in a first modification of the present embodiment, the gas supply holes  250   a  and  250   b  are respectively formed so as to face the inner wall of the reaction tube  203 , namely to face the electrode  300  rather than the wafer  200 , such that a gas is supplied to a side opposite to the wafers  200 . In addition, a supply flow rate of the gas and an exhaust amount of the gas are controlled such that the main flow of the gas inside the reaction tube  203  is oriented in a direction parallel to the surfaces of the wafers  200 , i.e., a horizontal direction. With this configuration, it is possible to supply a reaction gas toward the electric field  304 , thus efficiently generating plasma and easily generating active species in the wafers  200 . 
     Second Modification 
     Further, as illustrated in  FIGS. 7A to 7E , in a second modification of the present embodiment, irregularities are formed in the inner wall of the reaction tube  203  such that the surface area of the inner wall of the reaction tube  203  is increased. With this configuration, it is possible to reduce the density of active species having high kinetic energy, thus increasing the supply amount of active species having low kinetic energy inside the reaction tube  203 . For example, as illustrated in  FIG. 7A , hemispherical concave portions  203   a  are formed in the inner wall of the reaction tube  203 . As illustrated in  FIG. 7B , hemispherical convex portions  203   b  are formed in the inner wall of the reaction tube  203 . As illustrated in  FIG. 7C , rectangular convex portions  203   c  are formed in the inner wall of the reaction tube  203 . As illustrated in  FIG. 7D , conical convex portions  203   d  are formed in the inner wall of the reaction tube  203 . As illustrated in  FIG. 7E , truncated conical convex portions  203   e  is formed in the inner wall of the reaction tube  203 . Similarly, irregularities may be formed in the surface of the electrode  300 . 
     The embodiments of the present disclosure have been concretely described above. However, the present disclosure is not limited to the above-described embodiments but may be modified in different ways without departing from the spirit and scope of the present disclosure. 
     Further, for example, in the above embodiments, the example in which the reactant is supplied after the supply of the precursor has been described. The present disclosure is not limited to such an aspect. For example, the order of supply of the precursor and the reactant may be reversed. That is to say, the precursor may be supplied after the supply of the reactant. By changing the supply order in this way, it is possible to change the quality and composition ratio of a film to be formed. 
     In the above-described embodiments and the like, the example in which the SiO film is formed on the wafer  200  has been described. However, the present disclosure is not limited to such an aspect but may be suitably applied to a case of forming a Si-based oxide film such as a silicon oxycarbide film (SiOC film), a silicon oxycarbonitride film (SiOCN film), a silicon oxynitride film (SiON film) or the like on the wafer  200 . 
     For example, alternative to or in addition to the aforementioned gases, a nitrogen (N)-containing gas such as an ammonia (NH 3 ) gas, a carbon (C)-containing gas such as a propylene (C 3 H 6 ) gas, a boron (B)-containing gas such as a boron trichloride (BCl 3 ) gas, or the like may be used to form, for example, a SiN film, a SiON film, a SiOCN film, a SiOC film, a SiCN film, a SiBN film, a SiBCN film, a BCN film, or the like. The order of flow of each gas may be changed as appropriate. Even when these films are formed, the same process conditions as in the above embodiments may be applied. This provides the same effects as those in the above embodiments. In these cases, the aforementioned reaction gas may be used as an oxidizing agent as the reaction gas. 
     In addition, the present disclosure can be suitably applied to a case of forming a metal-based oxide film or metal-based nitride film containing a metal element such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), tungsten or the like on the wafer  200 . That is to say, the present disclosure can be suitably applied to a case of forming a TiO film, a TiOC film, a TiOCN film, a TiON film, a TiN film, a TiBN film, a TiBCN film, a ZrO film, a ZrOC film, a ZrOCN film, a ZrON film, a ZrN film, a ZrBN film, a ZrBCN film, an HfO film, an HfOC film, an HfOCN film, an HfON film, an HfN film, an HfBN film, an HfOCN film, a TaO film, a TaOC film, a TaOCN film, a TaON film, a TaN film, a TaBN film, a TaBCN film, an NbO film, an NbOC film, an NbOCN film, an NbON film, an NbN film, an NbBN film, an NbBCN film, an AlO film, an AlOC film, an AlOCN film, an AlON film, an AlN film, an AlBN film, an AlBCN film, an MoO film, an MoOC film, an MoOCN film, an MoON film, an MoN Film, an MoBN film, an MoBCN film, a WO film, a WOC film, a WOCN film, a WON film, a WN film, a WBN film, a WBCN film or the like on the wafer  200 . 
     In these cases, for example, as the precursor gas, a tetrakis(dimethylamino)titanium (Ti[N(CH 3 ) z ] 4 , abbreviation: TDMAT) gas, a tetrakis(ethylmethylamino)hafnium (Hf[N(C 2 H 5 )(CH 3 )] 4 , abbreviation: TEMAH) gas, a tetrakis(ethylmethylamino)zirconium (Zr[N(C 2 H 5 )(CH 3 )] 4 , abbreviation: TEMAZ) gas, a trimethylaluminum (Al(CH 3 ) 3 , abbreviation: TMA) gas, a titanium tetrachloride (TiCl 4 ) gas, a hafnium tetrachloride (HfCl 4 ) gas or the like may be used. 
     That is to say, the present disclosure can be suitably applied to a case of forming a half-metal-based film containing a half-metal element, and a metal-based film containing a metal element. Film forming processes of these films have the same process procedures and process conditions as those described in the above embodiments and modifications. These cases provide the same effect as in the above embodiments. 
     Recipes used in the substrate processing process may be provided individually according to the process contents and may be stored in the memory device  121   c  via a telecommunication line or the external memory device  123 . Moreover, at the start of a variety of processes, the CPU  121   a  may properly select an appropriate recipe from the recipes stored in the memory device  121   c  according to the process contents. Thus, it is possible for a single substrate processing apparatus to form thin films of different kinds, composition ratios, qualities and thicknesses for general purposes and with enhanced reproducibility. In addition, it is possible to reduce an operator&#39;s burden and to quickly start the variety of processes while avoiding an operation error. 
     The recipes mentioned above are not limited to newly-prepared ones but may be provided by, for example, modifying the existing recipes already installed in the substrate processing apparatus. When modifying the recipes, the modified recipes may be installed in the substrate processing apparatus via a telecommunication line or a recording medium storing the recipes. In addition, the existing recipes already installed in the substrate processing apparatus may be directly modified by operating the input/output device  122  of the existing substrate processing apparatus. 
     According to the present disclosure in some embodiments, it is possible to provide a technique for facilitating a uniform substrate process. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosures. Indeed, the novel methods and apparatuses described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the disclosures. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosures.