Patent Publication Number: US-2015075423-A1

Title: Spiral coating apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2013-193286, filed on Sep. 18, 2013; the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a spiral coating apparatus. 
     BACKGROUND 
     A spiral coating apparatus is an apparatus that forms a film on a substrate in the fields of, for example, semiconductors, etc. The spiral coating apparatus forms the film on the entire surface of a substrate having a discal configuration by fixing the substrate to a rotating stage having a circular configuration, rotating the stage, and moving a coating nozzle in a straight line from the substrate center toward the outer circumference of the substrate while dispensing a material from the coating nozzle to trace a coating path having a helical configuration (a spiral configuration). At this time, the thickness of the film can be more uniform by controlling the distance between the coating nozzle tip surface (the dispensing surface) and the substrate surface with high precision to be substantially constant. 
     Because the thickness of the film fluctuates when the tip of the coating nozzle is dirty, generally, the spiral coating apparatus cleans the matter adhered to the coating nozzle after the film is formed by using, for example, a cleaning liquid of an organic solvent, etc. However, the thickness of the film at the portion where the coating is started fluctuates when the cleaning liquid remains on the tip of the coating nozzle. The cleaning process of the coating nozzle is complex. Therefore, it is desirable to simplify the cleaning process of the coating nozzle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic plan view showing a spiral coating apparatus according to an embodiment of the invention; 
         FIG. 2A  and  FIG. 2B  are schematic views showing the nozzle cleaner of the embodiment; 
         FIG. 3A  to  FIG. 3F  are schematic plan views describing the effects of the nozzle cleaner and a method for cleaning the nozzle; 
         FIG. 4A  to  FIG. 4F  are schematic plan views showing a method for cleaning the nozzle according to a comparative example; 
         FIG. 5A  and  FIG. 5B  are schematic plan views showing a modification of the nozzle cleaner of the embodiment; and 
         FIG. 6A  and  FIG. 6B  are schematic plan views showing a specific example of the wiping unit of the embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     In general, according to one embodiment, a spiral coating apparatus includes: a stage; a nozzle; a movement unit; a gas supply unit; a cleaning liquid supply unit; and a nozzle cleaner. The stage has a placement surface configured to have a coating object placed on the placement surface. The nozzle is configured to dispense a liquid onto the coating object placed on the stage. The movement unit is configured to move the nozzle relative to the stage. The movement unit includes a first movement mechanism part and a second movement mechanism part. The first movement mechanism part is configured to move the nozzle in a direction parallel to a rotational axis of the stage. The second movement mechanism part is configured to move the nozzle along the placement surface in a direction intersecting the rotational axis. The gas supply unit is configured to supply a gas. The cleaning liquid supply unit is configured to supply a cleaning liquid. The nozzle cleaner has a gas supply port and a cleaning liquid supply port. The nozzle cleaner is configured to force the gas supplied by the gas supply unit from the gas supply port toward the nozzle and dispense the cleaning liquid supplied by the cleaning liquid supply unit from the cleaning liquid supply port toward the nozzle. 
     Embodiments of the invention will now be described with reference to the drawings. Similar components in the drawings are marked with like reference numerals, and a detailed description is omitted as appropriate. 
       FIG. 1  is a schematic plan view showing a spiral coating apparatus according to an embodiment of the invention. 
     The spiral coating apparatus  100  shown in  FIG. 1  includes a stage  101 , a nozzle  102 , a coating liquid supply unit  103 , a sensor  104 , a movement unit  105 , a nozzle cleaner  110 , a gas supply unit  14 , a cleaning liquid supply unit  20 , and a wiping unit  30 . 
     A substrate W is placed on a placement surface  101   a  of the stage  101  as a coating object. The stage  101  holds the substrate W that is placed. The stage  101  is formed in, for example, a circular configuration and is rotatable by a drive unit  107  in a horizontal plane (in a plane along the placement surface  101   a ). The substrate W is held by the stage  101  by, for example, a suction mechanism using a not-shown vacuum pump, etc. 
     The drive unit  107  supports the stage  101  to be rotatable in the horizontal plane and rotates the stage  101  in the horizontal plane with the center of the stage  101  as the center of rotation by, for example, a motor, etc. Thereby, the substrate W that is placed on the stage  101  is rotated in the horizontal plane. 
     The nozzle  102  dispenses a coating liquid L from the tip of the nozzle  102  toward the surface of the substrate W. The nozzle  102  coats the coating liquid L onto the surface of the substrate W by continuously dispensing the coating liquid L. For example, the substrate W is a semiconductor wafer, etc. For example, the coating liquid L is a resist liquid, etc. 
     The coating liquid supply unit  103  supplies the coating liquid L to the surface of the substrate W via the nozzle  102 . For example, the coating liquid supply unit  103  includes a tank, a pump, a supply valve, and a dispensing valve. The tank contains the coating liquid L. The pump supplies the coating liquid L to the nozzle  102 . The supply valve and the dispensing valve are opened and closed based on a signal transmitted from a not-shown controller to control the supply of the coating liquid L to the surface of the substrate W. 
     The sensor  104  senses the distance to the surface of the substrate W or the placement surface  101   a  of the stage  101 . The distance between a tip surface (a dispensing surface)  102   a  of the nozzle  102  and the surface of the substrate W is controlled by the not-shown controller based on the sensed distance to the surface of the substrate W. Or, the distance between the tip surface  102   a  of the nozzle  102  and the placement surface  101   a  of the stage  101  is controlled by the not-shown controller based on the sensed distance to the placement surface  101   a  of the stage  101 . For example, a reflection-type laser sensor, etc., may be used as the sensor  104 . 
     The movement unit  105  includes a lifting/lowering part (a first movement mechanism part)  105   a  and a movement part (a second movement mechanism part)  105   b  and moves the nozzle  102  relative to the stage  101 . The lifting/lowering part  105   a  holds the nozzle  102  and lifts and lowers the nozzle  102 . That is, the lifting/lowering part  105   a  moves the nozzle  102  in a direction parallel to the rotational axis of the stage  101 . The movement part  105   b  holds the lifting/lowering part  105   a  and moves the nozzle  102  in a direction orthogonal to the lifting/lowering direction. That is, the movement part  105   b  moves the nozzle  102  along the placement surface  101   a  in a direction perpendicular to the rotational axis of the stage  101 . For example, a robot having biaxial control, etc., may be used as the movement unit  105 . 
     The nozzle cleaner  110  cleans the tip portion of the nozzle  102  using a gas  202  supplied by the gas supply unit  14  and a cleaning liquid  201  supplied by the cleaning liquid supply unit  20 . Details of the nozzle cleaner  110  are described below. 
     The gas supply unit  14  includes a supply unit  14   a,  a pressure control unit  14   b,  and an open/close valve  14   c  and supplies the gas  202  to the nozzle cleaner  110  via a gas supply flow channel  14   d.  The supply unit  14   a  is, for example, factory piping, a tank that contains the high-pressure gas  202 , etc. The pressure control unit  14   b  controls the pressure of the gas  202  supplied by the supply unit  14   a  to be within a prescribed range. The open/close valve  14   c  controls the supply and cut-off of the gas  202 . 
     In such a case, a set that includes the pressure control unit  14   b  and the open/close valve  14   c  may be multiply provided. In the case where the set that includes the pressure control unit  14   b  and the open/close valve  14   c  is multiply provided, the flow velocity of the gas  202  that is forced can be switched according to the viscosity of the matter adhered to the nozzle  102 , etc. 
     For example, for adhered matter having a low viscosity, the gas  202  can be forced via the pressure control unit  14   b  that has a low pressure setting. For adhered matter having a high viscosity, the gas  202  can be forced via the pressure control unit  14   b  that has a high pressure setting. Thereby, the adhered matter having the high viscosity can be removed easily; and scattering of the adhered matter having the low viscosity can be suppressed. 
     The cleaning liquid supply unit  20  includes a container  22 , a liquid feed unit  23 , and a flow rate control unit  24  and supplies the cleaning liquid  201  to the nozzle cleaner  110  via a cleaning liquid supply flow channel  20   a.    
     The container  22  contains the cleaning liquid  201 . The cleaning liquid  201  is not particularly limited and may be appropriately selected according to the material properties of the adhered matter. For example, in the case where the adhered matter is a resist, the cleaning liquid  201  includes a ketone solvent, an alcohol solvent, etc. 
     The liquid feed unit  23  forces the cleaning liquid  201  contained in the container  22  toward the nozzle cleaner  110  by supplying a gas to the interior of the container  22 . 
     The liquid feed unit  23  includes a pressure control unit  23   a,  an open/close valve  23   b,  and a supply unit  23   c.    
     The pressure control unit  23   a  controls the pressure of the gas supplied by the supply unit  23   c  to the interior of the container  22 . The gas supplied by the supply unit  23   c  is not particularly limited, and includes, for example, air, nitrogen gas, etc. 
     The open/close valve  23   b  performs the supply and cut-off of the gas to the container  22 . 
     The supply unit  23   c  is, for example, factory piping, a tank that contains a high-pressure gas, etc. 
     The flow rate control unit  24  includes a flow regulating valve  24   a  and an open/close valve  24   b.    
     The flow regulating valve  24   a  regulates the flow rate of the cleaning liquid  201  supplied to the nozzle cleaner  110 . 
     The open/close valve  24   b  performs the supply and cut-off of the cleaning liquid  201  to the nozzle cleaner  110 . 
       FIG. 2A  and  FIG. 2B  are schematic views showing the nozzle cleaner of the embodiment. 
       FIG. 2A  is a schematic plan view showing the nozzle cleaner of the embodiment.  FIG. 2B  is a schematic cross-sectional view of the cross-section A-A shown in  FIG. 2A . 
     The nozzle cleaner  110  of the embodiment includes a housing  111  and a lifting/lowering mechanism part (a third movement mechanism part)  119 . 
     The housing  111  is, for example, a container, etc., having a hollow configuration. As shown in  FIG. 2A  and  FIG. 2B , at least a portion of the nozzle  102  is inserted into the interior of the housing  111 . That is, the housing  111  covers at least a portion of the outer circumference of the nozzle  102 . 
     The lifting/lowering mechanism part  119  holds the housing  111  and lifts and lowers the housing  111 . That is, the lifting/lowering mechanism part  119  lifts and lowers the housing  111  relative to the nozzle  102  in a direction parallel to the axis of the nozzle  102 . The lifting/lowering mechanism part  119  is held by the movement part  105   b  and can move in a direction orthogonal to the lifting/lowering direction. That is, the lifting/lowering mechanism part  119  can move with the nozzle  102  along the placement surface  101   a  in a direction perpendicular to the rotational axis of the stage  101 . Thereby, the nozzle cleaner  110  of the embodiment can move in the lifting/lowering direction relative to the nozzle  102  and can move with the nozzle  102  along the placement surface  101   a  in a direction perpendicular to the rotational axis of the stage  101 . 
     The housing  111  has a gas passage  113  and a cleaning liquid passage  115 . 
     One end of the gas passage  113  is connected to the gas supply flow channel  14   d.  The other end of the gas passage  113  is a gas supply port  113   a.  For example, the gas passage  113  is provided in an annular configuration around the entire circumference of the nozzle  102 . Or, the gas passage  113  may be multiply disposed around the entire circumference of the nozzle  102  at a prescribed spacing. As illustrated by arrows A 1  and A 2  of  FIG. 2A , the gas  202  that is supplied via the gas supply flow channel  14   d  and the gas passage  113  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102 . 
     One end of the cleaning liquid passage  115  is connected to the cleaning liquid supply flow channel  20   a.  The other end of the cleaning liquid passage  115  is used as a cleaning liquid supply port  115   a.  For example, the cleaning liquid passage  115  is provided in an annular configuration around the entire circumference of the nozzle  102 . Or, the cleaning liquid passage  115  may be multiply disposed around the entire circumference of the nozzle  102  at a prescribed spacing. As illustrated by arrows A 3  and A 4  of  FIG. 2A , the cleaning liquid that is supplied via the cleaning liquid supply flow channel  20   a  and the cleaning liquid passage  115  is dispensed from the cleaning liquid supply port  115   a  toward the tip portion of the nozzle  102 . 
     As shown in  FIG. 2A , the gas supply port  113   a  is provided to be higher than the cleaning liquid supply port  115   a.    
       FIG. 3A  to  FIG. 3F  are schematic plan views describing the effects of the nozzle cleaner and a method for cleaning the nozzle. 
       FIG. 4A  to  FIG. 4F  are schematic plan views showing a method for cleaning the nozzle according to a comparative example. 
     First, the method for cleaning the nozzle according to the comparative example will be described with reference to  FIG. 4A  to  FIG. 4F . 
     As shown in  FIG. 4A , a gas is appropriately forced onto the tip portion of the nozzle  102  to which adhered matter  211  is adhered. Continuing as shown in  FIG. 4B , the movement unit  105  moves the nozzle  102  to insert the tip portion of the nozzle  102  into the cleaning liquid  201  contained in a cleaning bath  221 . Then, the coating liquid L is dispensed from the nozzle  102 . Because the tip portion of the nozzle  102  is inserted into the cleaning liquid  201 , the cleaning liquid  201  mixes into the coating liquid L at the tip portion of the nozzle  102 . Therefore, the coating liquid L into which the cleaning liquid  201  is mixed is discharged. 
     Continuing as illustrated by arrow A 11  of  FIG. 4B  and as shown in  FIG. 4C , the movement unit  105  moves the nozzle  102  to insert the nozzle  102  into a blowing container  223 . Then, as illustrated by arrow A 13  and arrow A 14  of  FIG. 4C , a gas is forced from a jet hole  223   a  of the blowing container  223  onto the tip portion of the nozzle  102 . 
     Continuing as illustrated by arrow A 12  of  FIG. 4C , the movement unit  105  moves the nozzle  102  above the wiping unit  30 . Then, as illustrated by arrow A 15  and arrow A 16  of  FIG. 4D , the tip surface  102   a  of the nozzle  102  is wiped by bringing the tip surface  102   a  of the nozzle  102  into contact with the cloth part of the wiping unit  30  and moving the tip surface  102   a  over the cloth part of the wiping unit  30  in the contacting state. 
     Continuing as shown in  FIG. 4E , the movement unit  105  moves the nozzle  102  and leaves the nozzle  102  idle as-is. Thereby, the cleaning liquid  201  that is adhered to the tip surface  102   a  of the nozzle  102  and the tip portion of the nozzle  102  is dried. Continuing as shown in  FIG. 4F , the movement unit  105  moves the nozzle  102  above the stage  101  and performs the spiral coating. 
     Thus, in the method for cleaning the nozzle  102  according to the comparative example, the cleaning liquid  201  that is adhered to the tip surface  102   a  of the nozzle  102  and the tip portion of the nozzle  102  is dried by leaving the nozzle  102  idle. Therefore, the cleaning process of the nozzle  102  may take a relatively long time. Also, the movement of the nozzle  102  may take a relatively long time when, for example, the nozzle  102  is moved from the cleaning bath  221  to the blowing container  223 . 
     Conversely, in the embodiment, the spiral coating apparatus  100  includes the nozzle cleaner  110 . As described above in regard to  FIG. 2A  and  FIG. 2B , the nozzle cleaner  110  can move relative to the nozzle  102  in the lifting/lowering direction and can move with the nozzle  102  along the placement surface  101   a  in the direction perpendicular to the rotational axis of the stage  101 . 
     The method for cleaning the nozzle  102  of the embodiment will now be described with reference to  FIG. 3A  to  FIG. 3F . 
     As illustrated by arrow A 21  and arrow A 22  of  FIG. 3B , the gas  202  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102  in the state in which the adhered matter  211  is adhered to the tip portion of the nozzle  102  as shown in  FIG. 3A . 
     Continuing, the cleaning liquid  201  is dispensed from the cleaning liquid supply port  115   a  toward the tip portion of the nozzle  102  as illustrated by arrow A 23  and arrow A 24  of  FIG. 3C  while the gas  202  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102  as illustrated by, for example, arrow A 21  and arrow A 22  of  FIG. 3C . Thereby, the cleaning liquid  201  reaches substantially the entire circumference of the tip portion of the nozzle  102 . 
     Then, as illustrated by arrow A 21 , arrow A 22 , and arrow A 25  of  FIG. 3D , the lifting/lowering mechanism part  119  lowers the housing  111  toward the tip portion of the nozzle  102  while forcing the gas  202  from the gas supply port  113   a  toward the tip portion of the nozzle  102 . Thereby, the cleaning liquid  201  that is adhered to substantially the entire circumference of the tip portion of the nozzle  102  is blown off. 
     Continuing, the nozzle  102  is moved above the wiping unit  30  by the movement unit  105  while the gas  202  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102 . As described above, the gas supply port  113   a  is provided to be higher than the cleaning liquid supply port  115   a.  Thereby, the cleaning liquid  201  that re-adheres to and remains on the tip portion of the nozzle  102  after the cleaning liquid  201  adhered to the tip portion of the nozzle  102  is blown off by the gas  202  can be suppressed. 
     As illustrated by arrow A 21 , arrow A 22 , and arrow A 26  of  FIG. 3E , the lifting/lowering mechanism part  119  lifts the housing  111  toward the side opposite to the tip portion of the nozzle  102  while the gas  202  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102 . Continuing, for example, the tip surface  102   a  of the nozzle  102  is wiped by bringing the tip surface  102   a  of the nozzle  102  into contact with the cloth part of the wiping unit  30  and moving the tip surface  102   a  over the cloth part of the wiping unit  30  in the contacting state as illustrated by arrow A 27  of  FIG. 3E  while the gas  202  is forced from the gas supply port  113   a  toward the tip portion of the nozzle  102  as illustrated by arrow A 21  and arrow A 22  of  FIG. 3E . 
     Continuing as shown in  FIG. 3F , the gas  202  that was being forced from the gas supply port  113   a  is stopped; the nozzle  102  is moved above the stage  101  by the movement unit  105 ; and the spiral coating is performed. 
     According to the embodiment, the process of drying the tip portion of the nozzle  102  by leaving the nozzle  102  idle can be omitted. Therefore, the time for the cleaning process of the nozzle  102  can be reduced; and the cleaning process of the nozzle  102  can be simplified. Also, the gas  202  can be continuously forced from the gas supply port  113   a  toward the tip portion of the nozzle  102  partway through moving the nozzle  102 , partway through wiping the tip surface  102   a  of the nozzle  102  with the wiping unit  30 , etc. Thereby, the drying can be promoted; and the time for the cleaning process of the nozzle  102  can be reduced. 
     Also, because the cleaning bath  221  described above in regard to  FIG. 4B  is unnecessary, the spiral coating apparatus  100  can be compact; and the spiral coating apparatus  100  can be simplified. Further, because the cleaning liquid  201  is dispensed onto the tip portion of the nozzle  102  and the gas  202  is forced onto the tip portion of the nozzle  102 , the cleaning efficiency of the nozzle  102  can be higher than in the case where the tip portion of the nozzle  102  is inserted into the cleaning liquid  201  contained in the cleaning bath  221 . 
       FIG. 5A  and  FIG. 5B  are schematic plan views showing a modification of the nozzle cleaner of the embodiment. 
       FIG. 5A  is a schematic plan view showing an example of the modification of the nozzle cleaner.  FIG. 5B  is a schematic plan view showing another example of the modification of the nozzle cleaner. 
     A nozzle cleaner  110   a  shown in  FIG. 5A  has a cleaning liquid passage  117 . The cleaning liquid passage  117  is provided at the outer circumferential portion of the lower end portion of the housing  111 . One end of the cleaning liquid passage  117  is connected to the cleaning liquid supply flow channel  20   a.  The other end of the cleaning liquid passage  117  is used as a cleaning liquid supply port  117   a.  For example, the cleaning liquid passage  117  is provided in an annular configuration around the entire circumference of the tip portion of the nozzle  102 . Or, the cleaning liquid passage  117  may be multiply disposed around the entire circumference of the tip portion of the nozzle  102  at a prescribed spacing. As illustrated by arrow A 31  and arrow A 32  of  FIG. 5A , the cleaning liquid that is supplied via the cleaning liquid supply flow channel  20   a  and the cleaning liquid passage  117  is squirted from the cleaning liquid supply port  117   a  toward the tip portion of the nozzle  102 . Otherwise, the structure is similar to the structure of the nozzle cleaner  110  described above in regard to  FIG. 2A  and  FIG. 2B . 
     According to the modification, the nozzle cleaner  110   a  squirts the cleaning liquid  201  from the cleaning liquid supply port  117   a  toward the tip portion of the nozzle  102 . Therefore, the cleaning liquid  201  can reach substantially the entire circumference of the tip portion of the nozzle  102  more reliably. It is favorable for the gas  202  that is forced from the gas supply port  113   a  to be a laminar flow when flowing through the housing  111 . Thereby, the coating liquid L at the tip portion of the nozzle  102  that is sucked from the nozzle  102  by the flow of the gas  202  can be suppressed. 
     Compared to the nozzle cleaner  110   a  shown in  FIG. 5A , a nozzle cleaner  110   b  shown in  FIG. 5B  further includes a pedestal  118 . Thereby, the gas  202  that is forced from the gas supply port  113   a  can easily have a laminar flow when flowing through the housing  111 . Thereby, the coating liquid L at the tip portion of the nozzle  102  that is sucked from the nozzle  102  by the flow of the gas  202  can be suppressed more easily. 
     A specific example of the wiping unit  30  of the embodiment will now be described with reference to the drawings. 
       FIG. 6A  and  FIG. 6B  are schematic plan views showing a specific example of the wiping unit of the embodiment. 
       FIG. 6A  is a schematic cross-sectional view of the cross-section C-C shown in  FIG. 6B .  FIG. 6B  is a schematic cross-sectional view of the cross-section B-B shown in  FIG. 6A . 
     As shown in  FIG. 6A  and  FIG. 6B , the wiping unit  30  includes a base  31 , supports  32 , guides  33 , holders  34 , a pad  35 , elastic parts  36 , support plates  37 , pressing plates  38 , a cloth part  39 , a supply unit  40 , and a take-up unit  41 . 
     The base  31  has a plate configuration and is provided between the supply unit  40  and the take-up unit  41 . 
     The supports  32  are provided respectively at the two longitudinal-direction end portions of the base  31 . The supports  32  have columnar configurations. 
     The guides  33  are provided at the supports  32 . The guides  33  extend in the axis direction of the supports  32 . 
     The holders  34  hold the pad  35  and move along the guides  33 . 
     The pad  35  contacts the side of the cloth part  39  opposite to the side which the tip surface of the nozzle  102  contacts. The pad  35  has a plate configuration; and the two end portions of the pad  35  are held by the holders  34 . The longitudinal direction of the pad  35  is the same as the longitudinal direction of the base  31 . 
     The elastic parts  36  are provided between the base  31  and the pad  35  and urge the pad  35  toward the cloth part  39 . The elastic parts  36  are, for example, compression springs, etc. 
     The support plates  37  contact the side of the cloth part  39  opposite to the side which the tip surface of the nozzle  102  contacts. Two support plates  37  are provided with the pad  35  interposed in a direction orthogonal to the longitudinal direction of the pad  35 . The support plates  37  are held by, for example, the supports  32 . 
     The pressing plates  38  are provided respectively above the two support plates  37 . In other words, the pressing plates  38  are provided to face the support plates  37  with the cloth part  39  interposed between the pressing plates  38  and the support plates  37 . The pressing plates  38  are urged toward the support plates  37  by not-shown elastic parts. 
     Although the case is shown in which two sets of the support plate  37  and the pressing plate  38  are provided, the number of sets may be modified appropriately. For example, one set of the support plate  37  and the pressing plate  38  may be provided; or three or more sets may be provided. 
     The cloth part  39  has a band configuration. One end of the cloth part  39  is held by a roll  40   a  of the supply unit  40 ; and the other end of the cloth part  39  is held by a roll  41   a  of the take-up unit  41 . 
     The cloth part  39  passes between the support plate  37  and the pressing plate  38  on the supply unit  40  side, over the upper surface of the pad  35 , and between the support plate  37  and the pressing plate  38  on the take-up unit  41  side. 
     The tip surface of the nozzle  102  can be wiped by bringing the tip surface of the nozzle  102  into contact with the cloth part  39  and moving the tip surface over the cloth part  39  in the contacting state. At this time, the cloth part  39  is pressed onto the tip surface of the nozzle  102  by the pad  35  due to the effect of the elastic parts  36 . Therefore, the adhesion between the cloth part  39  and the tip surface of the nozzle  102  can be maintained. 
     The supply unit  40  holds the roll  40   a  onto which the cloth part  39  is wound. The roll  40   a  is rotatable. 
     The take-up unit  41  holds the roll  41   a.  The cloth part  39  is taken up by the roll  41   a  being rotated by a not-shown drive apparatus. 
     In the wiping unit  30  of the embodiment, the cloth part  39  is interposed between the support plates  37  and the pressing plates  38 . Therefore, sagging of the cloth part  39  between the supply unit  40  side and the take-up unit  41  side can be suppressed even in the case where the pad  35  is pressed by the nozzle  102  and the position of the pad  35  moves downward. Therefore, the adhered matter that is adhered to the nozzle  102  can be removed effectively. 
     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 inventions. Indeed, the novel embodiments 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 inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.