Patent Publication Number: US-2015072075-A1

Title: Film-forming apparatus and film-forming method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is continuation of PCT/JP2013/063632, filed May 16, 2013, which is based upon and claims the benefit of priority to Japanese Patent Application No. 2012-112653, filed May 16, 2012. The entire contents of these applications are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Embodiments of the disclosure relate to a film-forming apparatus and a film-forming method. 
     2. Description of Background Art 
     There is a film-forming method in which fine particles of a raw material are generated by aerosolizing a solution that contains the raw material and vaporizing a solvent in the aerosol, and are attached to a substrate, thereby forming a thin film on the substrate (see Japanese Patent No. 3541294). Specifically, in the technology described in Japanese Patent No. 3541294, a thin film is formed on a substrate by performing, for multiple times while shifting a line, a scan coating operation in which coating is performed by moving the substrate in a certain direction while discharging fine particles from a nozzle toward the substrate. In the technology described in Japanese Patent No. 3541294, the scan coating operation is performed using a nozzle on which a circular discharge port is formed. The entire contents of this publication are incorporated herein by reference. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a film-forming apparatus includes an aerosol generation device which generates an aerosol including a solution of a film-forming material dispersed in a carrier gas, a chamber which vaporizes the aerosol such that fine particles of the film-forming material are generated from the aerosol that is generated by the aerosol generation device, a nozzle which discharges the fine particles generated by the chamber toward a substrate, and a moving mechanism which executes relative movement of the nozzle and the substrate along a surface of the substrate. The nozzle has a discharge port which discharges the fine particles to a slit-shaped region extending in a direction orthogonal to a moving direction of the relative movement between the nozzle and the substrate executed by the moving mechanism. 
     According to another aspect of the present invention, a method for forming a film includes generating an aerosol including a solution of a film-forming material dispersed in a carrier gas by an aerosol generation device, vaporizing the aerosol in a chamber such that fine particles of the film-forming material is generated from the aerosol that is generated by the aerosol generation device, and discharging the fine particles generated by the chamber from a nozzle toward a substrate. The discharging of the fine particles includes discharging the fine particles to a slit-shaped region extending in a direction orthogonal to a movement direction of relative movement of the nozzle and the substrate while a moving mechanism executes the relative movement of the nozzle and the substrate along a surface of the substrate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
         FIG. 1  illustrates a schematic diagram illustrating a structure of a film-forming apparatus according to a first embodiment; 
         FIG. 2A  illustrates a schematic plan view illustrating a shape of a nozzle according to the first embodiment; 
         FIG. 2B  illustrates a schematic side view illustrating the shape of the nozzle according to the first embodiment; 
         FIG. 3A  illustrates a schematic diagram illustrating an operation example of a scan coating operation; 
         FIG. 3B  illustrates a schematic diagram illustrating an operation example of a scan coating operation; 
         FIG. 3C  illustrates a schematic diagram illustrating an operation example of a scan coating operation; 
         FIG. 4  illustrates a block diagram of the film-forming apparatus; 
         FIG. 5  illustrates a flow chart illustrating processing steps of a film-forming process that the film-forming apparatus executes; 
         FIG. 6  illustrates a schematic diagram illustrating a structure of a film-forming apparatus according to a second embodiment; 
         FIG. 7A  illustrates a schematic diagram illustrating an operation example of a scan coating operation according to the second embodiment; 
         FIG. 7B  illustrates a schematic diagram illustrating an operation example of a scan coating operation according to the second embodiment; 
         FIG. 7C  illustrates a schematic diagram illustrating an operation example of a scan coating operation according to the second embodiment; 
         FIG. 8  illustrates a schematic diagram illustrating a connection relationship between a first chamber and a recovery part according to a third embodiment; 
         FIG. 9A  illustrates a schematic plan view illustrating another shape of a nozzle; and 
         FIG. 9B  illustrates a schematic plan view illustrating another shape of a nozzle. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The embodiments will now be described with reference to the accompanying drawings, wherein like reference numerals designate corresponding or identical elements throughout the various drawings. 
     First Embodiment 
       FIG. 1  illustrates a schematic diagram illustrating a structure of a film-forming apparatus according to a first embodiment. A film-forming apparatus  1  illustrated in  FIG. 1  is a device that forms on a substrate (W) an organic thin film that forms an organic EL (Electro-Luminescence) element. The film-forming apparatus  1  includes an aerosol generation part  11 , a first chamber  12 , a pipe  13 , a nozzle  14 , a stage  15 , and a second chamber  16 . 
     In the following, in order to clarify a positional relation, mutually orthogonal X-axis, Y-axis and Z-axis are defined and a positive direction of the Z-axis is defined as being vertically upward. 
     The aerosol generation part  11  is a member that generates an aerosol (S) that is obtained by dispersing a solution of an organic material that is a film-forming material in a carrier gas. 
     The organic material contained in the aerosol (S) is, for example, polyphenylene vinylene (MEH-PPV), polyfluorene, tris-quinolinolate aluminum, or the like, but is not limited to these and can be any compound that is dissolved or dispersed at a concentration of about 0.001% in a solvent. In the following, the solution of the organic material is referred to as a “raw material solution.” Further, the carrier gas is an inert gas such as a nitrogen gas, an argon gas and a helium gas, or air. 
     The aerosol generation part  11  includes a gas supply part  111 , a raw material solution storage part  112 , a raw material solution supply part  113 , a filter  114 , pipes  115 ,  116 , and a spraying device  117   
     The gas supply part  111  supplies the carrier gas via the pipe  115  to the spraying device  117 . The gas supply part  111  includes, for example, a gas cylinder that stored the carrier gas and a controller that is connected to the gas cylinder and controls a flow rate and pressure of the carrier gas. 
     The raw material solution storage part  112  is a tank that stores the raw material solution and is connected via the pipe  116  to the spraying device  117 . The raw material solution that is stored in the raw material solution storage part  112  is sucked up from the raw material solution storage part  112  by the raw material solution supply part  113  that is provided at a middle portion of the pipe  116  and is supplied to the spraying device  117 . The raw material solution supply part  113  includes, for example, a pump and a controller controlling the pump. 
     At a middle portion of the pipe  116 , the filter  114  is provided. The filter  114  is, for example, a filter having an opening diameter of 0.5 μm and removes foreign substances contained in the raw material solution. 
     The spraying device  117  mixes and sprays the carrier gas that is supplied from the gas supply part  111  and the raw material solution that is supplied from the raw material solution storage part  112 , and thereby generates the aerosol (S) in which the raw material solution is suspended as liquid particles of sizes of about 1-100 μm in the carrier gas. 
     The spraying device  117  is fixed in a state in which a front end part thereof including a spray port penetrates through a base end part of the first chamber  12  and protrudes into the first chamber  12 . As a result, the aerosol (S) that is generated by the aerosol generation part  11  is supplied into the first chamber  12 . 
     Here, the aerosol generation part  11  uses the spraying device  117  to generate the aerosol S. However, it is also possible that the aerosol generation part uses a member other than the spraying device to generate the aerosol (S). For example, it is also possible that the aerosol generation part uses ultrasonic vibration to generate the aerosol. 
     The first chamber  12  is a container that has a cylindrical guide passage. The first chamber  12  is formed to have a large diameter so as not to hinder a flow of the aerosol S. A circular opening part is formed at a front end part of the first chamber  12 , and one end part of the pipe  13  is connected to the opening part. The pipe  13  is, for example, a rubber pipe. The first chamber  12  and the nozzle  14  are connected by the pipe  13 . 
     A heating part  121  such as an electric heater is provided on an outer peripheral surface of the first chamber  12 . Due to the heating part  121 , a temperature in the first chamber  12  is maintained at a temperature suitable for vaporization of the solvent contained in the aerosol (S). 
     The aerosol S that is supplied by the aerosol generation part  11  into the first chamber  12  is sent from the base end part to the front end part of the first chamber  12  by the carrier gas that is supplied from the gas supply part  111 . During this process, the solvent contained in the aerosol (S) is removed by vaporization and, as a result, fine particles of the organic material having particle diameters of about 10-1000 nm are generated. The generated fine particles of the organic material are supplied from the front end part of the first chamber  12  via the pipe  13  to the nozzle  14 . 
     The first chamber  12  is installed in a vertical orientation, that is, an orientation in which the base end part becomes a bottom part. As a result, among the generated fine particles of the organic material, particles having large particle diameters fall due to gravity and are unlikely to reach the front end part of the first chamber  12 . Therefore, by arranging the first chamber  12  in the vertical orientation, the particle diameters of the fine particles of the organic material that are supplied to the nozzle  14  can be equalized. 
     The nozzle  14  is a member that is arranged above the stage  15  that holds the substrate (W) in a horizontal orientation, and discharges the fine particles of the organic material toward a surface of the substrate (W) on the stage  15 . The stage  15  is, for example, a suction holding part that suction-holds the substrate (W), and moves in horizontal directions (X-axis direction and Y-axis direction) due to a moving mechanism (to be described later). 
     In the first embodiment, the substrate (W) is a glass substrate on a surface of which an indium tin oxide transparent conductive thin film (hereinafter referred to as an “ITO thin film”) is formed. The substrate (W) may also be a glass substrate on a surface of which a thin film of a metal such as gold or aluminum is formed, or a substrate other than a glass substrate such as a silicon substrate. 
     The nozzle  14 , the stage  15  and the substrate (W) are arranged in the second chamber  16 . The second chamber  16  includes an exhaust part  161 . From the exhaust part  161 , the carrier gas, the fine particles of the organic material that are not applied to the substrate (W), and the like, are discharged. 
     The film-forming apparatus  1  performs scan coating with respect to the substrate (W) by using the moving mechanism to move the stage  15  while discharging the fine particles of the organic material from the nozzle  14  toward the surface of the substrate (W). As a result, the fine particles of the organic material are attached to the surface of the substrate (W) and an organic thin film is formed. 
     In the case where a scan coating operation is performed, when the discharge port has a circular shape, it is difficult to perform coating in a broad area in one scan coating operation. Therefore, in the film-forming apparatus  1  according to the first embodiment, the discharge port of the nozzle  14  is formed in a slit shape and thereby coating in a broad area can be performed in one coating operation. 
     In the film-forming apparatus  1  according to the first embodiment, by devising not only the shape of the discharge port but also a shape of the nozzle  14  itself, film thickness uniformity is improved. 
     The specific shape of the nozzle  14  is described using  FIG. 2A and 2B .  FIG. 2A  illustrates a schematic plan view illustrating the shape of the nozzle  14  according to the first embodiment; and  FIG. 2B  illustrates a schematic side view illustrating the shape of the nozzle  14 . 
       FIG. 2A  illustrates a shape of a bottom part  141  of the nozzle  14  when viewed from above. The discharge port  142  of the nozzle  14  is formed on the bottom part  141 . 
     As illustrated in  FIG. 2A , the discharge port  142  extends in a direction orthogonal to a main scanning direction (X-axis direction) in a scan coating operation. That is, the discharge port  142  is formed wide with respect to the main scanning direction and thus a coating area per one scan coating operation can be increased as compared to a case where the same scan coating operation is performed using a circular discharge port having the same opening area. 
     The fine particles of the organic material tend to flow along an edge surface of the discharge port. Therefore, when a space between one edge and another edge of the discharge port is large, the fine particles of the organic material are less likely to attach to a portion of the surface of the substrate (W) positioned below this space and thus there is a concern that uneven coating occurs between the portion of the surface of the substrate (W) positioned below this space and portions of the surface of the substrate (W) positioned below the edges of the discharge port. 
     In contrast, the discharge port  142  of the nozzle  14  according to the first embodiment is formed narrow with respect to a direction (that is, a sub-scanning direction) that is orthogonal to the main scanning direction. That is, two edges of the discharge port  142  that extend in the sub-scanning direction (Y-axis direction) are close to each other. Therefore, the uneven coating as described above can be suppressed and film thickness uniformity can be improved. 
     The discharge port  142  is not necessarily required to have a slit shape. That is, the discharge port  142  may have a shape other than a slit shape as long as the discharge port  142  is formed in a slit-shaped region (R) that extends in a direction orthogonal to the main scanning direction. It is desirable that a width of the slit-shaped region (R) in the sub-scanning direction be 1 mm or less. 
     For the nozzle  14  according to the first embodiment, in addition to the discharge port  142 , the shape of the nozzle  14  is also devised. This point is described using  FIG. 2B . As illustrated in  FIG. 2B , the nozzle  14  has a cylindrical body part  143 , and the bottom part  141  is formed on one end of the body part  143 . As described above, the nozzle  14  is a bottomed cylindrical member, of which the discharge port  142  is formed on the bottom part  141 . On the other end of the body part  143 , the pipe  13  is connected. 
     An inner periphery of the body part  143  is formed in a cylindrical shape with an inner diameter (L 1 ) being substantially the same as an inner diameter (L 2 ) of the pipe  13 . In this way, in the first embodiment, a flow path of the fine particles of the organic material from the front end part of the first chamber  12  to the discharge port  142  of the nozzle  14  is formed to have substantially the same inner diameter. 
     When there is a place in the path from the front end part of the first chamber  12  to the discharge port  142  of the nozzle  14  where the inner diameter is different, there is a possibility that, at such a place, turbulence occurs in the flow of the fine particles and the fine particles are not uniformly discharged from the discharge port  142  so that uneven coating occurs. 
     As in the film-forming apparatus  1  according to the first embodiment, by making the inner diameter (L 1 ) of the body part  143  substantially the same as the inner diameter (L 2 ) of the pipe  13 , uneven coating can be suppressed and film thickness uniformity can be improved. 
     As illustrated in  FIG. 2B , the bottom part  141  of the nozzle  14  is formed thin. When the bottom part  141  is formed thick, the discharge port  142  also becomes thick and, as a result, there is a possibility that the fine particles of the organic material attach to inside of the discharge port  142  and clogging, turbulence in air flow, and the like, occur. 
     As in the film-forming apparatus  1  according to the first embodiment, by forming the bottom part  141  of the nozzle  14  thin, uneven coating can be further suppressed and film thickness uniformity can be improved. 
     Specifically, when a thickness (T) of the bottom part  141  was 3 mm, uneven coating was confirmed. However, when the thickness T was 1 mm, uneven coating was not confirmed. Therefore, the thickness (T) of the bottom part  141  is preferably less than 3 mm and is more preferably 1 mm or less. 
     Scan coating operations by the film-forming apparatus  1  are described using  FIG. 3A-3C .  FIG. 3A-3C  illustrate schematic diagrams illustrating operation examples of scan coating operations. 
     As illustrated in  FIG. 3A , the film-forming apparatus  1  moves the stage  15  in the main scanning direction, that is, a direction orthogonal to an extension direction of the discharge port  142  in a state in which the fine particles of the organic material are discharged from the discharge port  142 . As a result, the fine particles of the organic material are attached to the surface of the substrate (W) and an organic thin film (M) is formed. Here, an example is illustrated of a case where the organic thin film (M) is formed on one half of the surface of the substrate (W) by one scan coating operation. 
     As illustrated in  FIG. 3B , the film-forming apparatus  1  aligns a position of the discharge port  142  with respect to a portion of the surface of the substrate (W) on which application of the fine particles has not been performed, by moving the stage  15  in the sub-scanning direction, that is, a direction parallel to the extension direction of the discharge port  142 . 
     As illustrated in  FIG. 3C , the film-forming apparatus  1  again moves the stage  15  in the main scanning direction. As a result, the fine particles of the organic material are attached to the entire surface of the substrate (W) and the organic thin film (M) is formed on the entire surface of the substrate (W). 
     As described above, in the film-forming apparatus  1  according to the first embodiment, the nozzle  14  having the slit-shaped discharge port  142  is used to perform the scan coating to the substrate (W). Therefore, coating in a broad area can be performed in one scan coating operation. 
     Since coating in a broad area can be performed in one scan coating operation, as compared to a case where coating is performed using a nozzle that has a circular discharge port, the number of scan coating operations can be reduced and occurrence of uneven coating due to overlapping coating or coating failure can be suppressed. 
     Here, an example is illustrated of a case where the fine particles of the organic material are applied to the entire surface of the substrate (W) by two scan coating operations. However, the number of the scan coating operations varies depending on a diameter of the substrate (W) to be processed, a slit length of the discharge port  142 , and the like, and is not limited to two. 
     The structure of the film-forming apparatus  1  is described using  FIG. 4 .  FIG. 4  illustrates a block diagram of the film-forming apparatus  1 . In  FIG. 4 , structural elements for describing features of the film-forming apparatus  1  are illustrated; and description for general structural elements is omitted. 
     As illustrated in  FIG. 4 , the film-forming apparatus  1  includes the gas supply part  111 , the raw material solution supply part  113 , the heating part  121 , a moving mechanism  151 , a controller  20  and a memory  30 . Further, the controller  20  includes a flow rate controller  21 , a temperature controller  22  and a movement controller  23 . The memory  30  stores setting information  31 . 
     In addition to the structural elements illustrated in  FIG. 4 , the film-forming apparatus  1  also includes the raw material solution storage part  112 , the spraying device  117 , the first chamber  12 , the nozzle  14 , and the like that are illustrated in  FIG. 1 , but these are omitted in  FIG. 4 . 
     The moving mechanism  151  moves the stage  15  in horizontal directions, specifically, the main scanning direction (X-axis direction) and the sub-scanning direction (Y-axis direction). This allows the position of the discharge port  142  of the nozzle  14  to relatively change along the surface of the substrate (W) that is placed on the stage  15 . 
     The moving mechanism  151  can also move the stage  15  in the vertical direction (Z-axis direction). This allows a distance between the surface of the substrate (W) and the nozzle  14  to change. 
     The moving mechanism  151  includes a drive source such as a motor and uses the drive source to move the stage  15 . 
     The controller  20  is a controller that controls the whole film-forming apparatus  1 , and includes the flow rate controller  21 , the temperature controller  22  and the movement controller  23 . 
     The flow rate controller  21  is a processing part that controls the flow rate of the carrier gas that is supplied from the gas supply part  111  to the spraying device  117  by controlling the controller of the gas supply part  111 . 
     The flow rate of the carrier gas is controlled by the flow rate controller  21 . Thereby, the flow rate and the pressure of the carrier gas are ensured that allow the fine particles of the organic material to be guided from the front end part of the first chamber  12  to the surface of the substrate (W). 
     The flow rate controller  21  also performs processing that controls a flow rate of the raw material solution that is supplied from the raw material solution storage part  112  to the spraying device  117  by controlling the controller of the raw material solution supply part  113 . The flow rate controller  21  determines the flow rates of the carrier gas and the raw material solution according to the setting information  31  stored in the memory  30 . 
     The temperature controller  22  is a processing part that controls a heating temperature due to the heating part  121 . The heating temperature is controlled by the temperature controller  22 . Thereby, the temperature in the first chamber  12  is maintained at the temperature suitable for the vaporization of the solvent contained in the aerosol (S). The temperature controller  22  determines the heating temperature according to the setting information  31  stored in the memory  30 . 
     The movement controller  23  is a processing part that controls the movement of the stage  15  by controlling the drive source of the moving mechanism  151 . The moving mechanism  151  is controlled by the movement controller  23 . Thereby, the movement of the stage  15  in the horizontal directions (the main scanning direction and the sub-scanning direction) and the vertical direction is controlled. 
     The memory  30  is storage device such as a nonvolatile memory or a hard disk drive, and stores the setting information  31 . The setting information  31  is information that includes the flow rate of the carrier gas, the flow rate of the raw material solution, the heating temperature due to the heating part  121 , the distance between the nozzle  14  and the stage  15 , a movement speed of the stage  15 , and the like. The setting information  31  may be appropriately changed by an operation from a user. 
     A specific operation of the film-forming apparatus  1  is described using  FIG. 5 .  FIG. 5  illustrates a flow chart illustrating processing steps of a film-forming process that the film-forming apparatus  1  executes. 
     As illustrated in  FIG. 5 , first, the temperature controller  22  turns on the heating part  121  (S 101 ); and the flow rate controller  21  turns on the gas supply part  111  and the raw material solution supply part  113  (S 102 ). As a result, heating by the heating part  121  is started, and supply of the carrier gas and the raw material solution to the spraying device  117  is started and the fine particles of the organic material begin to be discharged from the nozzle  14 . 
     The controller  20  judges whether or not a predetermined period of time has passed since the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  are turned on (S 103 ), and, when the predetermined period of time has not passed (No at S 103 ), waits until the predetermined period of time has passed (S 104 ). When the film-forming apparatus  1  is waiting, the stage  15  is in a state being retreated to a position where the fine particles discharged from the nozzle  14  are not applied to the substrate (W). 
     Immediately after the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  are turned on, there is a possibility that particle diameters and a discharge rate of the fine particles of the organic material are not stable and uneven coating occurs on the surface of the substrate (W). Therefore, after the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  are turned on, the film-forming apparatus  1  does not start the scan coating operation until the predetermined period of time has passed. Thereby, occurrence of the uneven coating can be prevented. The above-described predetermined period of time is, for example, 10 seconds. 
     At S 103 , when it is judged that the predetermined period of time has passed (Yes at S 103 ), the movement controller  23  starts to move the stage  15  by controlling the moving mechanism  151  (S 105 ). As a result, the scan coating operations illustrated in  FIG. 3A-3C  are executed. 
     The film-forming apparatus  1  according to the first embodiment includes the aerosol generation part  11 , the first chamber  12 , the nozzle  14  and the moving mechanism  151 . The aerosol generation part  11  generates the aerosol (S) that is obtained by dispersing the solution of the raw material that is the film-forming material in the carrier gas. In the first chamber  12 , the aerosol (S) that is generated by the aerosol generation part  11  is supplied from the base end part, and, by vaporizing the supplied aerosol (S), the fine particles of the organic material that is the film-forming material are generated. The nozzle  14  discharges toward the substrate (W) the fine particles that are released from the front end part of the first chamber  12 . The moving mechanism  151  relatively moves the nozzle  14  and the substrate (W) along the surface of the substrate (W). 
     The nozzle  14  has the discharge port  142  for the fine particles in the slit-shaped region (R) that extends in a direction orthogonal to the direction of the movement due to the moving mechanism  151 . Therefore, according to the film-forming apparatus  1  of the first embodiment, coating efficiency can be improved. 
     According to a film-forming method that the film-forming apparatus  1  executes, an organic thin film can be formed even without conditions such as high temperature and vacuum. 
     For example, from a raw material solution that is obtained by dissolving or dispersing in a solvent a polymer material for which film formation using a vacuum deposition method is difficult, a metal complex that changes in quality when heated, and the like, a thin film of these organic materials can be formed. Further, even from an aerosol that is formed from a dilute raw material solution of 0.1% or less for which film formation in a wet process is difficult, by performing vaporization of the solvent before attaching the organic material to the substrate, an organic thin film that can be used for an organic EL element can be formed. 
     Second Embodiment 
     In the above-described first embodiment, an example is described of a case where the film-forming apparatus includes one nozzle. However, a film-forming apparatus can also use multiple nozzles to form a thin film of multiple layers on the surface of the substrate (W) in one scan coating operation. In the following, an example is described of a case where a film-forming apparatus includes multiple nozzles. 
     A structure of a film-forming apparatus according to a second embodiment is described using  FIG. 6 .  FIG. 6  illustrates a schematic diagram illustrating the structure of the film-forming apparatus according to the second embodiment. In the following description, a part that is the same as a part that has already been described is indicated using the reference numeral symbol as the part that has already been described, and redundant description is omitted. 
     As illustrated in  FIG. 6 , a film-forming apparatus  1   a  according to the second embodiment includes a substrate carrying part  17  (corresponding to a moving mechanism). The substrate carrying part  17  is, for example, a roller conveyor, and, by rotating a large number of rollers  171 , carries the substrate (W) that is placed on the rollers  171  in the main scanning direction (X-axis direction). The substrate carrying part  17  has a heating mechanism (not illustrated in  FIG. 6 ) such as a heater, and is capable of carrying the substrate (W) while heating the substrate (W). 
     The film-forming apparatus  1   a  according to the second embodiment includes three nozzles ( 14   a,    14   b,    14   c ). The nozzles ( 14   a,    14   b,    14   c ) are each the same as the nozzle  14  ( FIGS. 2A and 2B ) according to the first embodiment. 
     The nozzles ( 14   a,    14   b,    14   c ) are each arranged above the substrate carrying part  17  in a state in which the discharge port is oriented toward a carrying surface of the substrate carrying part  17 , and are arranged side by side at equal intervals along the main scanning direction. Further, similar to the first embodiment, a discharge port that is formed on each of the nozzles ( 14   a,    14   b,    14   c ) extends in a direction orthogonal to the main scanning direction. 
     The nozzles ( 14   a,    14   b,    14   c ), the substrate carrying part  17  and the substrate (W) are arranged in a second chamber ( 16   a ). Similar to the second chamber  16  according to the first embodiment, the second chamber ( 16   a ) includes an exhaust part  162 . From the exhaust part  162 , the carrier gas, the fine particles of the organic material that are not applied to the substrate (W), and the like, are discharged. 
     The nozzles ( 14   a,    14   b,    14   c ) are respectively connected via pipes ( 13   a - 13   c ) to front end parts of first chambers ( 12   a - 12   c ). Further, for the first chambers ( 12   a - 12   c ), aerosol generation parts ( 11   a - 11   c ) are respectively provided. 
     The aerosol generation parts ( 11   a - 11   c ) respectively include gas supply parts ( 111   a - 111   c ), raw material solution storage parts ( 112   a - 112   c ), raw material solution supply parts ( 113   a - 113   c ), filters ( 114   a - 114   c ), pipes ( 115   a - 115   c,    116   a - 116   c ) and spraying devices ( 117   a - 117   c ). 
     In the raw material solution storage part ( 112   a - 112   c ), raw material solutions that contain different organic materials are respectively stored. This allows aerosols containing different organic materials to be respectively supplied to the first chambers ( 12   a - 12   c ). As a result, fine particles of different organic materials are respectively supplied to the nozzles ( 14   a - 14   c ). 
     As described above, in the second embodiment, the nozzles ( 14   a,    14   b,    14   c ) are respectively connected to the different first chambers ( 12   a - 12   c ), and respectively discharge the fine particles of the different organic materials toward the substrate (W). 
     Structure of the aerosol generation parts ( 11   a - 11   c ), the first chambers ( 12   a - 12   c ) and the pipes ( 13   a - 13   c ) are the same as the aerosol generation part  11 , the first chamber  12  and the pipe  13  according to the first embodiment and thus descriptions thereof are omitted here. 
     An operation of the film-forming apparatus  1   a  according to the second embodiment is described using  FIG. 7A-7C .  FIG. 7A-7C  illustrate schematic diagrams illustrating operation examples of scan coating operations according to the second embodiment. 
     The film-forming apparatus  1   a  drives the substrate carrying part  17  to carry the substrate (W) in the main scanning direction (X-axis direction) in a state in which fine particles (P 1 -P 3 ) of the different organic materials are respectively discharged from the discharge ports of the nozzles ( 14   a - 14   c ). 
     As a result, as illustrated in  FIG. 7A-7C , the fine particles (P 1 ) of the organic material that are discharged from the nozzle ( 14   a ), the fine particles (P 2 ) of the organic material that are discharged from the nozzle ( 14   b ) and the fine particles (P 3 ) of the organic material that are discharged from the nozzle ( 14   c ) are respectively applied in this order on the surface of the substrate (W). As a result, on the surface of the substrate (W), three kinds of organic thin films (F 1 -F 3 ) are formed in laminated layers by one scan coating operation. 
     According to a film-forming method that the film-forming apparatuses ( 1 ,  1   a ) execute, multiple organic thin films can be laminated without causing interlayer mixing. Therefore, as in the film-forming apparatus  1   a  according to the second embodiment, the fine particles (P 1 -P 3 ) of the plurality of the organic materials can be applied in one scan coating operation. 
     In the second embodiment, the film-forming apparatus  1   a  includes the plurality of the nozzles ( 14   a,    14   b,    14   c ) that are arranged along the direction of the movement due to the substrate carrying part  17 . Therefore, the fine particles of the plurality of the organic materials can be applied in one scan coating operation. Therefore, when multiple thin films are formed on one substrate (W), for example, since there is no need to perform a setup change for the nozzle, time required for film formation can be shortened. 
     In the above-described second embodiment, an example is described of a case where the film-forming apparatus includes three nozzles. However, the number of the nozzles that the film-forming apparatus includes may be two or may be four or more. 
     In the above-described second embodiment, an example is described of a case where fine particles of different kinds of organic materials are respectively discharged from the nozzles. However, in a film-forming apparatus, it is also possible that fine particles of a same organic material are discharged from at least two of multiple nozzles. In this case, the nozzles from which the fine particles of the same organic material are discharged may be connected to a same first chamber. 
     Third Embodiment 
     The film-forming apparatus may include a recovery part that recovers the aerosol or the fine particles of the organic material in the first chamber. In the following, an example of a case where the film-forming apparatus includes a recovery part is described using  FIG. 8 .  FIG. 8  illustrates a schematic diagram illustrating a connection relationship between a first chamber and a recovery part according to a third embodiment. 
     As illustrated in  FIG. 8 , a film-forming apparatus ( 1   b ) according to the third embodiment further includes a recovery part  18 . The recovery part  18  includes a recovery container  181 , a pipe  182  and a valve  183 . The recovery container  181  is a container in which an aerosol or fine particles of an organic material that are recovered from the first chamber  12  are stored. The recovery container  181  is connected via the pipe  182  to the first chamber  12 . 
     At a middle portion of the pipe  182 , the valve  183  is provided. Further, also at a middle portion of the pipe  13  that is connected to the front end part of the first chamber  12 , a valve  131  is provided. Opening and closing of these valves ( 131 ,  183 ) are controlled by a controller of the film-forming apparatus ( 1   b ). 
     Immediately after the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  (see  FIG. 1 ) are turned on, the particle diameters and the discharge rate of the fine particles of the organic material are unlikely to be stable. Therefore, it is conceivable that, by keeping the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  (see  FIG. 1 ) in an always-on state, waiting time until the particle diameters and the discharge rate of the fine particles of the organic material become stable is reduced. However, an amount of the raw material solution that is wastefully consumed is increased. 
     The controller of the film-forming apparatus ( 1   b ) according to the third embodiment closes the valve  131  and opens the valve  183  during a period of time from when a last scan coating operation with respect to one substrate (W) is completed to when an initial scan coating operation with respect to a next substrate (W) is started. As a result, the aerosol that is supplied into the first chamber  12  and the fine particles of the organic material that are generated in the first chamber  12  are recovered via the pipe  182  to the recovery container  181  and thus that the aerosol and the fine particles of the organic material are wastefully consumed can be prevented. 
     The controller of the film-forming apparatus ( 1   b ) opens the valve  131  and closes the valve  183  at a timing when the initial scan coating operation with respect to the next substrate (W) is started. As a result, from the nozzle  14 , the fine particles of the organic material are discharged. In the third embodiment, the heating part  121 , the gas supply part  111  and the raw material solution supply part  113  (see  FIG. 1 ) are kept in an always-on state. Therefore, the fine particles of the organic material are discharged in a state in which the particle diameters and the discharge rate are stable. Therefore, the film-forming apparatus ( 1   b ) does not need to wait to start a scan coating operation until the particle diameters and the discharge rate of the fine particles of the organic material become stable. 
     The film-forming apparatus ( 1   b ) according to the third embodiment further includes the recovery part  18  that is connected to the first chamber  12  and recovers the aerosol or the fine particles of the organic material in the first chamber  12 . Therefore, even when generation of the aerosol by the aerosol generation part  11  is constantly performed, waste of the raw material solution can be suppressed. 
     Fourth Embodiment 
     The shape of the discharge port that is formed on the nozzle is not necessarily limited to the shape illustrated in  FIG. 2A . In the following, other examples of the shape of the discharge port are described using  FIGS. 9A and 9B .  FIGS. 9A and 9B  illustrate schematic plan views illustrating other shapes of nozzles. 
     For example, as illustrated in  FIG. 9A , it is also possible that a nozzle ( 14   d ) has two discharge ports ( 142   a,    142   b ) in a slit-shaped region (R). Here, an example is described of a case where the two discharge ports ( 142   a,    142   b ) are formed. However, it is also possible that two or more discharge ports are formed in the slit-shaped region (R). 
     It is not necessary that a discharge port is formed in a shape extending in the sub-scanning direction (Y-axis direction). For example, as illustrated in  FIG. 9B , a nozzle ( 14   e ) includes a large number of discharge ports ( 142   c ) in a slit-shaped region (R). It is also possible that each of the discharge ports ( 142   c ) in this case has a shape such that a length in the sub-scanning direction (Y-axis direction) and a length in the main scanning direction (X-axis direction) are the same, or the length in the main scanning direction is longer. 
     As described above, a discharge port may be formed in any shape as long as the discharge port is formed in the slit-shaped region (R) that extends in a direction orthogonal to the main scanning direction. 
     In the above-described embodiments, as illustrated in  FIG. 2B , an example is described of a case where a nozzle has cylindrical body part. However, it is also possible that a body part of a nozzle has a non-cylindrical shape. For example, it is also possible that a body part of a nozzle has a tapered shape in which an inner diameter on a discharge port side is smaller than an inner diameter on a pipe side. 
     In the above-described embodiments, an example is described of a case where the film-forming apparatus forms on a substrate an organic thin film that forms an organic EL element. However, the film-forming apparatus is not limited to the organic EL element, but is also applicable to cases where organic thin films forms other organic devices such as an organic FET (Field-Effect Transistor) and an organic optoelectronic conversion element. 
     In the above-described embodiments, an example is described of a case where an organic thin film is formed on a substrate using a moving mechanism to move the substrate. However, it is also possible that the film-forming apparatus forms an organic thin film on a substrate using a moving mechanism to move the nozzle. That is, the moving mechanism may be any mechanism that relatively moves the nozzle and the substrate along a surface of the substrate. However, when the nozzle is moved, due to deformation of the pipe that is connected to the nozzle, there is a possibility that turbulence occurs in the flow of the fine particles that move in the pipe. Therefore, it is preferable that the film-forming apparatus move the substrate rather than the nozzle. 
     When the discharge port that is formed on the nozzle has a circular shape, it is difficult to perform coating in a broad area in one scan coating operation. 
     A film-forming apparatus and a film-forming method according to an embodiment of the present invention can improve coating efficiency. 
     A film-forming apparatus according to an embodiment of the present invention includes an aerosol generation part, a chamber, a nozzle and a moving mechanism. The aerosol generation part generates an aerosol that is obtained by dispersing a solution of a film-forming material in a carrier gas. In the chamber, the aerosol that is generated by the aerosol generation part is supplied from a base end part, and, by vaporizing the supplied aerosol, fine particles of the film-forming material are generated. The nozzle discharges toward a substrate the fine particles that are released from a front end part of the chamber. The moving mechanism relatively moves the nozzle and a substrate along a surface of the substrate. Further, the nozzle has a discharge port for the fine particles in a slit-shaped region that extends in a direction orthogonal to a direction of movement due to the moving mechanism. 
     According to an embodiment of the present invention, coating efficiency can be improved. 
     Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.