Patent Publication Number: US-2022223442-A1

Title: Semiconductor manufacturing apparatus and control method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-003289; filed Jan. 13, 2021; the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a semiconductor manufacturing apparatus and a control method thereof. 
     BACKGROUND 
     For example, as a method of forming a high-quality film, there is a method of growing a film on a wafer (substrate) based on a chemical vapor deposition (CVD) method. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view showing a semiconductor manufacturing apparatus according to at least one embodiment. 
         FIGS. 2A and 2B  are schematic cross-sectional views showing a state of deposition of a deposit in a pipe according to at least one embodiment. 
         FIG. 3  is a schematic view showing an example of outputs of an acoustic sensor before and after cleaning an inside of the pipe in the semiconductor manufacturing apparatus according to at least one embodiment. 
         FIGS. 4A and 4B  are schematic diagrams showing an example of how to attach the acoustic sensor according to at least one embodiment. 
         FIG. 5  is a schematic cross-sectional diagram showing another example of how to attach the acoustic sensor according to at least one embodiment. 
         FIG. 6  is a schematic cross-sectional diagram showing another example of how to attach the acoustic sensor according to at least one embodiment. 
         FIG. 7  is a flowchart showing a control method of the semiconductor manufacturing apparatus according to at least one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     At least one embodiment provides a semiconductor manufacturing apparatus and a control method thereof that are capable of checking clogging of a pipe without stopping. 
     In general, according to at least one embodiment, a semiconductor manufacturing apparatus includes: a reaction chamber; a pipe connected to the reaction chamber; a vacuum pump that has an intake port and an exhaust port, and in which the intake port or the exhaust port is connected to the pipe; a first acoustic sensor provided in the pipe; and a control device (controller) including a determination unit configured to determine clogging of the pipe based on a first output of the first acoustic sensor. 
     According to at least one embodiment, a control method of a semiconductor manufacturing apparatus is a semiconductor manufacturing method using the semiconductor manufacturing apparatus. The semiconductor manufacturing apparatus includes: a reaction chamber; a pipe connected to the reaction chamber; a vacuum pump that has an intake port and an exhaust port, and in which the intake port or the exhaust port is connected to the pipe; and a first acoustic sensor provided in the pipe. The control method includes determining clogging of the pipe based on a first output of the first acoustic sensor. 
     An embodiment will be described below with reference to drawings. In the drawings, the same or similar locations are denoted by the same or similar reference numerals. 
     Embodiment 
     According to at least one embodiment, a semiconductor manufacturing apparatus includes: a reaction chamber, a pipe connected to the reaction chamber, a vacuum pump that has an intake port and an exhaust port, and in which the intake port or the exhaust port is connected to the pipe; a first acoustic sensor provided in the pipe; and a control device (controller) including a determination unit configured to determine clogging of the pipe based on a first output of the first acoustic sensor. 
     According to at least one embodiment, a control method of a semiconductor manufacturing apparatus is a semiconductor manufacturing method using the semiconductor manufacturing apparatus. The semiconductor manufacturing apparatus includes: a reaction chamber; a pipe connected to the reaction chamber; a vacuum pump that has an intake port and an exhaust port, and in which the intake port or the exhaust port is connected to the pipe; and a first acoustic sensor provided in the pipe. The control method includes determining clogging of the pipe based on a first output of the first acoustic sensor. 
       FIG. 1  is a schematic view of a semiconductor manufacturing apparatus  100  according to the embodiment. 
     The semiconductor manufacturing apparatus  100  includes a reaction chamber  2 , a support portion  4 , a vacuum pump  6 , a three-way valve  12 , a three-way valve  16 , a valve  22 , a valve  24 , a valve  26 , a valve  28 , a pipe  32 , a pipe  34 , a pipe  36 , a pipe  38 , a pipe  40 , a pipe  42 , an acoustic sensor  50 , an acoustic sensor  52 , a detoxifying device  60 , a control device  70  (controller), and an alarm device  90 . 
     The control device  70  includes a determination unit  72 , a threshold value storage unit  74 , a time interval storage unit  76 , a wafer processing number storage unit  78 , a conversion information storage unit  80 , and a reference output storage unit  82 . 
     The semiconductor manufacturing apparatus  100  according to at least one embodiment is, for example, an apparatus that grows a film on a wafer W such as a silicon wafer using a CVD method. 
       FIG. 1  shows a reaction chamber  2   a  and a reaction chamber  2   b  as the reaction chamber  2 . The growth of the film is performed in the reaction chamber  2 . A process gas supply mechanism  92  is connected to the reaction chamber  2 . The process gas supply mechanism  92  includes, for example, a gas generation unit, a gas cylinder, a pipe, a control valve, and a flow rate control mechanism such as a mass flow controller, which are not shown. The process gas supply mechanism supplies process gas into the reaction chamber  2 . The process gas is, for example, Tetraethyl Orthosilicate (TEOS) gas. The semiconductor manufacturing apparatus  100  forms a TEOS film (SiO 2  film) on the surface of the wafer W based on the CVD method using the process gas. In  FIG. 1 , the process gas supply mechanism  92  alone is connected to both the reaction chamber  2   a  and the reaction chamber  2   b.  However, an individual process gas supply mechanism  92  may be connected to each of the reaction chamber  2   a  and the reaction chamber  2   b.    
     In the reaction chamber  2 , a support portion  4  on which the wafer W can be placed and which rotates the wafer W in a circumferential direction of the wafer W is provided. In  FIG. 1 , a support portion  4   a  and a support portion  4   b  are provided in the reaction chamber  2   a.  A support portion  4   c  and a support portion  4   d  are provided in the reaction chamber  2   b.  As the support portion  4 , for example, a holder that has an opening portion at a center and supports a substrate at a peripheral edge is used. As the support portion  4 , a susceptor having no opening portion may be used. 
     Although the wafer W is, for example, a silicon wafer, the wafer may be a sapphire wafer or the like. In  FIG. 1 , a wafer W a  is provided on the support portion  4   a,  a wafer W b  is provided on the support portion  4   b,  a wafer W c  is provided on the support portion  4   c,  and a wafer W d  is provided on the support portion  4   d.    
     The number of reaction chamber  2 , a type of process gas, a type and the number of the support portions  4 , and a type and the number of the wafers W in the semiconductor manufacturing apparatus  100  are not limited to those described above. 
       FIG. 1  shows a vacuum pump  6   a  and a vacuum pump  6   b  as the vacuum pump  6 . The vacuum pump  6   a  includes an intake port  8   a  and an exhaust port  10   a.  The vacuum pump  6   b  includes an intake port  8   b  and an exhaust port  10   b.  The vacuum pump  6  is an exhaust system including, for example, a dry pump or a pressure gauge. 
     The pipe  32  is connected to the reaction chamber  2   a  and the intake port  8   a.  The pipe  34  is connected to the exhaust port  10   a.  The vacuum pump  6   a  intakes excess process gas and reaction byproducts in the reaction chamber  2   a  from the intake port  8   a  via the pipe  32 . Then, the vacuum pump  6   a  exhausts the excess process gas and the reaction byproducts from the exhaust port  10   a  to the pipe  34 . 
     The pipe  34  is connected to the valve  22 . Further, the pipe  34  is connected to the pipe  36  via the valve  22 . The pipe  36  includes a pipe part  36   a,  a pipe part  36   c,  a pipe part  36   e,  a curved portion  36   b  that connects the pipe part  36   a  and the pipe part  36   c,  and a curved portion  36   d  that connects the pipe part  36   c  and the pipe part  36   e.  The curved portion  36   b  and the curved portion  36   d  are, for example, elbows of pipes. The valve  22  is, for example, a ball valve or a butterfly valve. 
     The pipe  38  is connected to the reaction chamber  2   b  and the intake port  8   b.  The pipe  40  is connected to the exhaust port  10   b.  The vacuum pump  6   b  intakes excess process gas and reaction byproducts in the reaction chamber  2   b  from the intake port  8   b  via the pipe  38 . Then, the vacuum pump  6   a  exhausts the excess process gas and the reaction byproducts from the exhaust port  10   b  to the pipe  40 . 
     The pipe  40  is connected to the valve  26 . Further, the pipe  40  is connected to the pipe  42  via the valve  26 . The pipe  42  includes a pipe part  42   a,  a pipe part  42   c,  a pipe part  42   e,  a curved portion  42   b  that connects the pipe part  42   a  and the pipe part  42   c,  and a curved portion  42   d  that connects the pipe part  42   c  and the pipe part  42   e.  The curved portion  42   b  and the curved portion  42   d  are, for example, elbows of pipes. The valve  26  is, for example, a ball valve or a butterfly valve. 
     The number of the vacuum pumps  6 , a form of the pipes, and a form of the valves in the semiconductor manufacturing apparatus  100  are not limited to those described above. 
     The detoxifying device  60  detoxifies toxic gas and combustible gas that are discharged from the reaction chamber  2 . The detoxifying device  60  is, for example, a scrubber.  FIG. 1  shows a detoxifying device  60   a  and a detoxifying device  60   b  as the detoxifying device  60 . 
     The detoxifying device  60   a  is connected to the pipe part  36   e.  The pipe part  36   e  is connected to a port  14   a  of the three-way valve  12  via the valve  24  in the detoxifying device  60   a.  The valve  24  is, for example, a ball valve or a butterfly valve. A port  14   b  of the three-way valve  12  is connected to a combustion furnace (not shown) in the detoxifying device  60   a.  In the combustion furnace (not shown), the toxic gas and the combustible gas are detoxified. The port  14   c  of the three-way valve  12  is connected to, for example, a bypass line (not shown). Then, the toxic gas or the combustible gas detoxified by the combustion furnace is discharged through the bypass line (not shown). 
     The detoxifying device  60   b  is connected to the pipe part  42   e.  The pipe part  42   e  is connected to a port  18   a  of the three-way valve  16  via the valve  28  in the detoxifying device  60   b.  The valve  28  is, for example, a ball valve or a butterfly valve. A port  18   b  of the three-way valve  16  is connected to a combustion furnace (not shown) in the detoxifying device  60   b.  In the combustion furnace (not shown), the toxic gas and the combustible gas are detoxified. The port  18   c  of the three-way valve  16  is connected to, for example, a bypass line (not shown). Then, the toxic gas or the combustible gas detoxified by the combustion furnace is discharged through the bypass line (not shown). 
     The acoustic sensor  50  is provided outside the pipe  32 , the pipe  34 , or the pipe  36 . The acoustic sensor  50  is, for example, an acoustic emission (AE) sensor. The acoustic sensor  50  measures vibration of the pipe  32 , the pipe  34 , or the pipe  36 . Then, the acoustic sensor  50  outputs a result of the measured vibration to an outside of the acoustic sensor  50 . The output is an example of the first output or a second output. 
       FIG. 1  shows an acoustic sensor  50   a,  an acoustic sensor  50   b,  an acoustic sensor  50   c,  an acoustic sensor  50   d,  an acoustic sensor  50   e,  and an acoustic sensor  50   f  as the acoustic sensor  50 . The acoustic sensor  50   a  is provided, for example, on an upper side of the pipe  34 . The acoustic sensor  50   b  is provided, for example, on a lower side of the pipe part  36   a.  The acoustic sensor  50   c  is provided, for example, on a lower side of the curved portion  36   b.  The acoustic sensor  50   d  is provided, for example, on a side surface of the pipe part  36   c.  The acoustic sensor  50   e  is provided, for example, on an upper side of the pipe part  36   e.  The acoustic sensor  50   f  is provided, for example, on a side surface of the pipe  32 . 
     The acoustic sensor  52  is provided outside the pipe  38 , the pipe  40 , or the pipe  42 . The acoustic sensor  52  is, for example, an acoustic emission (AE) sensor. The acoustic sensor  52  measures vibration of the pipe  38 , the pipe  40 , or the pipe  42 . Then, the acoustic sensor  52  outputs a result of the measured vibration to an outside of the acoustic sensor  52 . The output is an example of the first output or the second output. 
       FIG. 1  shows an acoustic sensor  52   a,  an acoustic sensor  52   b,  an acoustic sensor  52   c,  an acoustic sensor  52   d,  an acoustic sensor  52   e,  and an acoustic sensor  52   f  as the acoustic sensor  52 . The acoustic sensor  52   a  is provided, for example, on an upper side of the pipe  40 . The acoustic sensor  52   b  is provided, for example, on a lower side of the pipe part  42   a.  The acoustic sensor  52   c  is provided, for example, on a lower side of the curved portion  42   b.  The acoustic sensor  52   d  is provided, for example, on a side surface of the pipe part  42   c.  The acoustic sensor  52   e  is provided, for example, on an upper side of the pipe part  42   e.  The acoustic sensor  52   f  is provided, for example, on a side surface of the pipe  38 . 
     The acoustic sensor  50  is an example of the first acoustic sensor or a second acoustic sensor. The acoustic sensor  52  is an example of the first acoustic sensor or the second acoustic sensor. 
     The acoustic sensor  50  and the acoustic sensor  52  preferably measure a sound having a frequency of 100 kHz or more and 200 kHz or less. 
       FIGS. 2A and 2B  is a schematic cross-sectional view showing a state of deposition of a deposit D in a pipe according to the embodiment. Arrows in  FIGS. 2A and 2B  indicate a positional relationship between a gravity direction and the deposit D in the pipe part  36   a.    
     In  FIG. 2A , the deposit D is uniformly deposited on an inner wall of the pipe part  36   a.  Therefore, a cross-sectional shape of a cavity C is circular. In  FIG. 2B , the deposit D is deposited inside the lower pipe part  36   a.  One of the reasons for such deposition is that the deposit D is more likely to be deposited downward due to gravity. In the pipe  34  and the pipe part  36   a  that are closer to the vacuum pump  6   a  with respect to the curved portion  36   b,  and in the pipe  40  and the pipe part  42   a  that are closer to the vacuum pump  6   b  with respect to the curved portion  42   b,  since the excess process gas is less likely to smoothly flow through the curved portion  36   b  or the curved portion  42   b,  the excess process gas is likely to stay inside. Therefore, in addition to an effect of gravity, the deposit D is more likely to be deposited downward. 
       FIG. 3  is a schematic view showing an example of outputs of the acoustic sensor before and after cleaning an inside of the pipe in the semiconductor manufacturing apparatus  100  according to at least one embodiment. The output of the acoustic sensor before the cleaning of the inside of the pipe is lower than the output of the acoustic sensor immediately after the cleaning of the inside of the pipe. The above indicates that a vibration of the pipe tends to decrease as the deposit D is deposited in the pipe. The above also indicates that a degree of deposition of the deposit D inside the pipe can be evaluated by evaluating the vibration of the pipe using the acoustic sensor. A reason why such evaluation is possible is considered to be that, when the deposit D is deposited in the pipe, molecules of the excess process gas flowing through the pipe do not directly collide with an inner wall of the pipe, and thus the vibration of the pipe is reduced. 
     For example, when the deposit D is deposited in the pipe, it is considered that the deposit D vibrates together with the pipe. In a state in which the deposit D is deposited in the pipe, in order to vibrate the pipe by the same degree as in a state in which the deposit D is not deposited in the pipe, it is considered that a larger vibration energy is required. Therefore, it is considered that a vibration of the pipe tends to decrease as the deposit D is deposited in the pipe. 
     According to the above, it is considered that the degree of deposition of the deposit D inside the pipe can be evaluated by evaluating the vibration of the pipe using the acoustic sensor. 
       FIGS. 4A and 4B  are schematic diagrams showing an example of how to attach the acoustic sensor according to at least one embodiment. In  FIGS. 4A and 4B , a Z direction is a direction opposite to the gravity direction. In  FIGS. 4A and 4B , an X direction is a direction that perpendicularly intersects the Z direction. The X direction is a direction in which the pipe part  36   a  extends. In  FIGS. 4A and 4B , the Y direction is a direction that perpendicularly intersects the X direction and the Z direction.  FIG. 4A  is a schematic cross-sectional diagram showing the example of how to attach the acoustic sensor according to the embodiment in a YZ plane. In  FIG. 4A , a wire  54   b  is also shown.  FIG. 4B  is a schematic diagram showing the example of how to attach the acoustic sensor according to the embodiment in an XY plane. For example, as the acoustic sensor  50   b  in  FIG. 4A , providing the acoustic sensor  50   b  on the lower side or a lower surface of the pipe part  36   a  is an example of a preferred aspect. 
     The acoustic sensor  50   b  is fixed to a lower surface of a plate  58  using, for example, a screw (not shown). A plate  56  and a plate  58  are fixed to each other using, for example, screws (not shown). The plate  56  and the plate  58  are, for example, metal plates. The plate member  56  is attached to the pipe part  36   a  using, for example, a wire  54   a  and the wire  54   b.  Further, the plate  56  and the pipe part  36   a  are in contact with each other at a contact portion  57 . A fixing portion  59  fixes the plate member  56  such that the plate member  56  does not slip on a surface of the pipe part  36   a.  In this manner, the acoustic sensor  50   b  is provided at the contact portion  57  of the pipe part  36   a  via the plate member  56  and the plate member  58 . The contact portion  57  is a part where a lower surface of the pipe part  36   a  and the plate  56  are in contact with each other. 
       FIG. 5  is a schematic cross-sectional diagram showing another example of how to attach the acoustic sensor according to the embodiment. In  FIG. 5 , a wire  54   b  is also shown. It is an example of a preferred aspect that an acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a,  and an acoustic sensor  50   b   2  is provided on an upper side or an upper surface of the pipe part  36   a.    
     In  FIG. 5 , the acoustic sensor  50   b   1  is fixed to a lower surface of a plate  58   a  using, for example, a screw (not shown). The plate  56   a  and the plate  58   a  are fixed to each other using, for example, screws (not shown). The plate  56   a  and the plate  58   a  are, for example, metal plates. The plate  56   a  is attached to the pipe part  36   a  using, for example, the wire  54   b.  The plate  56   a  and the pipe part  36   a  are in contact with each other at a contact portion  57   a.  A fixing portion  59   a  fixes the plate member  56   a  such that the plate member  56   a  does not slip on the surface of the pipe part  36   a.  In this manner, the acoustic sensor  50   b   1  is provided at the contact portion  57   a  of the pipe part  36   a  via the plate member  56   a  and the plate member  58   a.  The contact portion  57   a  is a part where the lower surface of the pipe part  36   a  and the plate  56   a  are in contact with each other. Therefore, in an aspect shown in  FIG. 5 , the acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a.    
     In  FIG. 5 , the acoustic sensor  50   b   2  is fixed to an upper surface of a plate  58   b  using, for example, a screw (not shown). A plate  56   b  and the plate  58   b  are fixed to each other using, for example, screws (not shown). The plate  56   b  and the plate  58   b  are, for example, metal plates. The plate  56   b  is attached to the pipe part  36   a  using, for example, the wire  54   b.  The plate  56   b  and the pipe part  36   a  are in contact with each other at a contact portion  57   b.  A fixing portion  59   b  fixes the plate member  56   b  such that the plate member  56   b  does not slip on the surface of the pipe part  36   a.  In this manner, the acoustic sensor  50   b   2  is provided at the contact portion  57   b  of the pipe part  36   a  via the plate member  56   b  and the plate member  58   b.  The contact portion  57   b  is a part where the upper surface of the pipe part  36   a  and the plate  56   b  are in contact with each other. Therefore, in the aspect shown in  FIG. 5 , the acoustic sensor  50   b   2  is provided on the upper side or the upper surface of the pipe part  36   a.    
     In  FIG. 5 , the contact portion  57   a  and the contact portion  57   b  are provided at positions facing each other. In other words, both the contact portion  57   a  and the contact portion  57   b  pass through a straight line passing through a center  37   a  of the pipe, which is indicated by a dotted line in  FIG. 5 . 
       FIG. 6  is a schematic cross-sectional diagram showing another example of how to attach the acoustic sensor according to the embodiment. In  FIG. 6 , the wire  54   b  is also shown. As shown in  FIG. 6 , it is an example of a preferred aspect that the acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a,  and the acoustic sensor  50   b   2  and an acoustic sensor  50   b   3  are disposed around the pipe part  36   a  in a manner of being separated from the acoustic sensor  50   b   1  by 120 degrees. 
     In  FIG. 6 , the acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a.  The acoustic sensor  50   b   2  is provided at a part deviated clockwise by 120 degrees in a plane perpendicular to the direction (X direction), in which the pipe part  36   a  extends, from a part of the pipe part  36   a  where the acoustic sensor  50   b   1  is provided. The acoustic sensor  50   b   3  is provided at a part deviated counterclockwise by 120 degrees in the plane perpendicular to the direction (X direction), in which the pipe part  36   a  extends, from the part of the pipe part  36   a  where the acoustic sensor  50   b   1  is provided. In other words, the acoustic sensor  50   b   3  is provided at a part deviated clockwise by 120 degrees in the plane perpendicular to the direction (X direction), in which the pipe part  36   a  extends, from a part of the pipe part  36   a  where the acoustic sensor  50   b   2  is provided. 
     For example, among the acoustic sensor  50   a,  the acoustic sensor  50   b,  the acoustic sensor  50   d,  and the acoustic sensor  50   e,  there is a high chance that the acoustic sensor  50   b  can obtain an output corresponding to the deposit D by the largest deposition amount. This is because the excess process gas is likely to remain inside since the pipe part  36   a  in which the acoustic sensor  50   b  is provided is located at a location closer to the reaction chamber  2   a  with respect to the curved portion  36   b  and is located at a location closer to the curved portion  36   b.    
     There is a high chance that the acoustic sensor  50   d  can obtain an output corresponding to the deposit D by a next largest deposition amount after the acoustic sensor  50   b.  This is because the excess process gas is likely to remain inside since the pipe part  36   c  is located at a location closer to the reaction chamber  2   a  with respect to the curved portion  36   d  and is located at a location closer to the curved portion  36   d.  However, a large amount of the deposit D is deposited inside the pipe part  36   a  in which the acoustic sensor  50   b  is provided, and then the process gas passes through the pipe part  36   c.  Therefore, it is considered that an amount of the deposit D in the pipe part  36   c  provided with the acoustic sensor  50   d  is smaller than an amount of the deposit D in the pipe part  36   a  provided with the acoustic sensor  50   b  by the amount of the deposit D deposited in the pipe part  36   a.    
     There is a high chance that the acoustic sensor  50   a  can obtain an output corresponding to the deposit D by a next largest deposition amount after the acoustic sensor  50   d.  This is because the pipe  34  in which the acoustic sensor  50   a  is provided is closer to the vacuum pump  6   a  with respect to the pipe part  36   e  in which the acoustic sensor  50   e  is provided, and thus it is considered that a gas containing a larger amount of reaction byproducts as the deposit D passes through the pipe  34 . 
     For the same reason, among the acoustic sensor  52   a,  the acoustic sensor  52   b,  the acoustic sensor  52   d,  and the acoustic sensor  52   e,  there is a high chance that the acoustic sensor  52   b  can obtain the output corresponding to the deposit D by the largest deposition amount. There is a high chance that the acoustic sensor  52   d  can obtain an output corresponding to the deposit D by a next largest deposition amount after the acoustic sensor  52   b.  There is a high chance that the acoustic sensor  52   a  can obtain an output corresponding to the deposit D by a next largest deposition amount after the acoustic sensor  52   d.    
     When the deposit D is deposited inside the pipe  34 , the pipe  34  is removed between the exhaust port  10   a  and the valve  22 , and the inside of the pipe  34  are cleaned. 
     When the deposit D is deposited inside the pipe  36 , the pipe  36  is removed between the valve  22  and the detoxifying device  60   a,  and the inside of the pipe  36  is cleaned. 
     When the deposit D is deposited inside the pipe  40 , the pipe  40  is removed between the exhaust port  10   b  and the valve  26 , and the inside of the pipe  40  is cleaned. 
     When the deposit D is deposited inside the pipe  42 , the pipe  42  is removed between the valve  26  and the detoxifying device  60   b,  and the inside of the pipe  42  is cleaned. 
     The determination unit  72  determines clogging of the pipe based on the output of the acoustic sensor  50  or the acoustic sensor  52 . 
     When the determination unit  72  determines that “the pipe is clogged” or makes other determinations, for example, the control device  70  or the determination unit  72  can stop a manufacturing process performed in the reaction chamber  2  or the vacuum pump  6 . 
     The threshold value storage unit  74  stores a threshold value for determining the clogging of the pipe. Then, the determination unit  72  determines the clogging of the pipe based on the threshold value. 
     The conversion information storage unit  80  has conversion information for converting the output of the acoustic sensor into a pipe clogging amount. Then, the determination unit  72  determines the clogging of the pipe based on the converted pipe clogging amount. Here, the conversion can be executed by, for example, the determination unit  72 . The conversion may not be executed. 
     For example, the conversion information storage unit  80  preferably has a plurality of pieces of conversion information. Here, the plurality of pieces of conversion information are prepared, for example, for each manufacturing process performed in the reaction chamber  2 . Then, for example, based on the manufacturing process described above, the determination unit  72  can appropriately use the corresponding conversion information among the plurality of conversion information to apply the conversion information to each of the plurality of acoustic sensors  50 , each of the plurality of acoustic sensors  52 , or each of the acoustic sensor  50  and the acoustic sensor  52 , and can determine the clogging of the pipe. For example, when the configuration of the film formed on the wafer W in the reaction chamber  2  is different, it can be considered that the manufacturing process performed in the reaction chamber  2  is different. Even when an exhaust amount of the vacuum pump  6  is different, it is considered that a way of accumulation of the deposit D is changed and away of clogging of the pipe is different, and thus different conversion information can be used. The above description is an example of “the conversion information storage unit has a plurality of pieces of conversion information used for each manufacturing process, and determines which of the plurality of pieces of conversion information is to be used based on the manufacturing process”. 
     The reference output storage unit  82  stores a reference output of an acoustic sensor provided in a pipe having no clogging. For example, the output of the acoustic sensor immediately after the cleaning of the inside of the pipe shown in  FIG. 3  is stored in the reference output storage unit  82  as the reference output. In this case, the determination unit  72  can determine the clogging of the pipe based on a difference between the output of the acoustic sensor and the reference output. The reference output storage unit  82  may be omitted. 
     The acoustic sensor  50  and the acoustic sensor  52  preferably execute output at predetermined time intervals. The predetermined time interval is stored in the time interval storage unit  76 . 
     The wafer processing number storage unit  78  stores the number of wafers W processed in the reaction chamber  2   a  and the reaction chamber  2   b.  In this case, the determination unit  72  can determine the clogging of the pipe based on the number of the wafers W. 
     For example, it is preferable that the determination unit  72  issues an alarm using the alarm device  90  based on the outputs of the acoustic sensor  50  or the acoustic sensor  52 . Here, the determination unit  72  may issue an alarm using the alarm device  90  based on the output of one acoustic sensor  50  or acoustic sensor  52 . For example, the determination unit  72  may issue an alarm based on outputs of a plurality of acoustic sensors  50  or acoustic sensors  52 . For example, a case is considered in which the semiconductor manufacturing apparatus  100  includes a total of four acoustic sensors  50  or acoustic sensors  52 . For example, when the number of the acoustic sensors  50  or the acoustic sensors  52  that issue an alarm is zero, it is determined that a pipe state is a state of “normal”, and the determination unit  72  may not issue an alarm using the alarm device  90 . For example, when the number of the acoustic sensors  50  or the acoustic sensors  52  that issue an alarm is two, it is determined that the pipe state is a state of “caution”, and the determination unit  72  may issue an alarm on the state of “caution” using the alarm device  90 . For example, when the number of the acoustic sensors  50  or the acoustic sensors  52  that issue an alarm is four, it is determined that the pipe state is a state in which a “replacement alarm” is to be issued, and the determination unit  72  may issue an alarm on the state using the alarm device  90 . For example, the determination unit  72  may control and issue different types of alarms such as the “normal”, the “caution”, and “replacement information” together with an increase in the number of wafers W stored in the wafer processing number storage unit  78  using the alarm device  90 . The above aspect is an example of “further including a second acoustic sensor and an alarm device, in which the determination unit issues an alarm using the alarm device based on the first output and the second output of the second acoustic sensor”. The alarm device  90  is, for example, a chime, a siren, a lamp, or a monitor such as a liquid crystal monitor. 
     The control device  70  and the determination unit  72  are, for example, electronic circuits. The control device  70  and the determination unit  72  are, for example, computers formed by a combination of hardware such as an arithmetic circuit and software such as a program. 
     The threshold value storage unit  74 , the time interval storage unit  76 , the wafer processing number storage unit  78 , the conversion information storage unit  80 , and the reference output storage unit  82  are, for example, semiconductor memories or hard disks. 
       FIG. 7  is a flowchart showing a control method of the semiconductor manufacturing apparatus  100  according to the embodiment. 
     First, the wafer W is placed on the support portion  4  in the reaction chamber  2 . Next, process gas is introduced into the reaction chamber  2  using the process gas supply mechanism  92  to form a film on the wafer W. The excess process gas and the reaction byproducts are exhausted by the vacuum pump  6 . 
     Next, for example, the determination unit  72  measures the vibration caused by the process gas flowing inside the pipe using the output of the acoustic sensor  50  or the output of the acoustic sensor  52 . The output and the measurement may be executed at predetermined time intervals using, for example, time stored in the time interval storage unit  76  (S 2 ). 
     Next, for example, the determination unit  72  converts the output of the acoustic sensor  50  or the output of the acoustic sensor  52  into the pipe clogging amount using the conversion information stored in the conversion information storage unit  80  (S 4 ). The conversion may not be executed. 
     Next, the determination unit  72  determines the clogging of the pipe, for example, based on an obtained conversion result (pipe clogging amount) and the threshold value stored in the threshold value storage unit  74 . For example, the determination unit  72  determines whether the pipe clogging amount is smaller than the threshold value (S 6 ). 
     When the pipe clogging amount is smaller than the threshold value, for example, the determination unit  72  further executes measurement by the acoustic sensor (S 2 ). On the other hand, when the pipe clogging amount is equal to or greater than the threshold value, for example, the determination unit  72  issues an alarm that “there is an abnormality in the pipe (there is a certain amount or more of clogging in the pipe)” using the alarm device  90 . 
     Next, functions and effects of the semiconductor manufacturing apparatus  100  and the control method of the semiconductor manufacturing apparatus  100  according to the embodiment will be described. 
     In the pipe connected to the semiconductor manufacturing apparatus  100 , the excess process gas, the reaction byproducts, and the like react inside the pipe and are deposited as the deposits D inside the pipe. In related arts, during an operation of the semiconductor manufacturing apparatus  100 , it is difficult to check the amount of the deposit D inside the pipe, and it is necessary to wait until replacement of the pipe or cleaning of the pipe is performed. Therefore, in related arts, a certain time interval is determined, and the pipe is always mechanically replaced at the time interval. However, in this case, the pipe may be replaced even though the inside of the pipe is not fairly clogged. Even though time is shorter than the time interval, the pipe may be clogged. 
     Therefore, according to at least one embodiment, the semiconductor manufacturing apparatus includes the reaction chamber  2 , the pipe connected to the reaction chamber  2 , the vacuum pump  6  that has the intake port  8  and the exhaust port  10 , and in which the intake port  8  or the exhaust port  10  is connected to the pipe, the acoustic sensor provided in the pipe, and the control device  70  including the determination unit  72  that determines clogging of the pipe based on the output of the acoustic sensor. 
     As described above, when the deposit D is deposited in the pipe, molecules of the excess process gas flowing through the pipe do not directly collide with the inner wall of the pipe, and thus the vibration of the pipe is reduced. Therefore, the clogging of the pipe can be determined based on the output of the acoustic sensor  50  or the acoustic sensor  52 . In this case, the clogging of the pipe can be checked without visually checking the inside of the pipe. Therefore, the clogging of the pipe can be checked without reducing an operation rate of the semiconductor manufacturing apparatus wastefully by, for example, stopping the semiconductor manufacturing apparatus and replacing the pipe. 
     For example, it is considered that the output of the acoustic sensor decreases with the clogging of the pipe. Therefore, for example, the determination unit  72  can determine, using the threshold value stored in the threshold value storage unit  74 , that the cleaning of the pipe is necessary when the output of the acoustic sensor is small to what degree. 
     A correlation relationship between the degree of the clogging of the pipe due to the deposit D or the like and the output of the acoustic sensor can be measured in advance, and the correlation relationship can be stored in the conversion information storage unit  80  as the conversion information. Accordingly, it is possible to monitor the degree of the clogging of the pipe in more detail. 
     It is preferable that a plurality of pieces of the conversion information is used for each manufacturing process, and which of the plurality of pieces of conversion information is to be used is determined based on the manufacturing process. When the configuration of the film formed on the wafer W in the reaction chamber  2  is different, or the exhaust amount of the vacuum pump  6  is different, it is considered that the way of the accumulation of the deposit D is changed and the way of the clogging of the pipe is different. Therefore, it is possible to monitor the degree of the clogging of the pipe in more detail. 
     It is preferable that the reference output storage unit  82  stores the reference output of the acoustic sensor provided in the pipe having no clogging. Since it is easy to compare the output of the pipe having no clogging with the reference output, it is possible to monitor the degree of the clogging of the pipe in more detail. 
     It is preferable that when the determination unit  72  determines that “the pipe is clogged” or makes other determinations, for example, the control device  70  or the determination unit  72  stops the manufacturing process performed in the reaction chamber  2  or the vacuum pump  6 . When the pipe is clogged, if manufacturing of the semiconductor is continued as it is, rupture or the like of the pipe may occur, which is dangerous. This risk can be avoided by stopping the manufacturing process performed in the reaction chamber  2  or the vacuum pump  6 . 
     It is preferable that the semiconductor manufacturing apparatus further includes the second acoustic sensor and the alarm device. The determination unit issues the alarm using the alarm device based on the first output and the second output of the second acoustic sensor. The above is because a level of how to issue the alarm can be classified, and an operator of the semiconductor manufacturing apparatus can determine the clogging of the pipe in more detail. 
     For example, it is preferable to determine, based on the manufacturing process, which of the plurality of pieces of conversion information is used for each of the plurality of acoustic sensors  50 , each of the plurality of acoustic sensors  52 , or each of the acoustic sensor  50  and the acoustic sensor  52 . In a case in which the configuration of the film formed on the wafer W in the reaction chamber  2  is different, in a case in which the exhaust amount of the vacuum pump  6  is different, or in other cases, it is considered that the way of the accumulation of the deposit D is changed and the way of the clogging of the pipe is different, and thus it is possible to monitor the degree of the clogging of the pipe in more detail. 
     The acoustic sensor  50  and the acoustic sensor  52  preferably measure the sound having the frequency of 100 kHz or more and 200 kHz or less. The above is because it is considered that the clogging of the pipe cannot be evaluated with a high SN ratio since the sound having a frequency of less than 100 kHz is considered to include a large amount of sound from another semiconductor manufacturing apparatus or the like provided around the semiconductor manufacturing apparatus  100 . A sound having a frequency higher than 200 kHz has an excessively high frequency and is difficult to be measured. 
     It is preferable that the semiconductor manufacturing apparatus further includes the wafer processing number storage unit  78  that stores the number of wafers processed in the reaction chamber  2 , and the determination unit  72  further determines the clogging based on the number of wafers. It is considered that there is a positive correlation relationship between the number of processed wafers and the clogging of the pipe. Therefore, by utilizing the number of processed wafers, it is possible to monitor the degree of the clogging of the pipe in more detail. 
     The acoustic sensor  50  and the acoustic sensor  52  preferably execute output at predetermined time intervals. This is because the clogging of the pipe can be prevented from being missed by executing the output at the predetermined time intervals. 
     For example, as in the acoustic sensor  50   b  in  FIG. 4A , providing the acoustic sensor  50   b  on the lower side or the lower surface of the pipe part  36   a  is preferred. The above is because, when the deposit D is deposited as shown in  FIG. 2B , the degree of deposition of the deposit D on the lower side in the pipe part  36   a,  in which the way of the deposition of the deposit D is larger, can be evaluated more favorably. 
     For example, as shown in  FIG. 5 , the acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a,  and the acoustic sensor  50   b   2  is provided on the upper side or the upper surface of the pipe part  36   a.  When the deposit D is deposited as shown in  FIG. 2B , the degree of deposition of the deposit D on the lower side in the pipe part  36   a,  in which the way of the deposition of the deposit D is larger, can be evaluated using the acoustic sensor  50   b   1 . The degree of deposition of the deposit D on the upper side in the pipe part  36   a,  in which the way of the deposition of the deposit D is smaller, can be evaluated using the acoustic sensor  50   b   2 . Accordingly, the degree of deposition of the deposit D can be evaluated on both the lower side and the upper side in the pipe part  36   a.    
     As shown in  FIG. 6 , it is preferable that the acoustic sensor  50   b   1  is provided on the lower side or the lower surface of the pipe part  36   a,  and the acoustic sensor  50   b   2  and the acoustic sensor  50   b   3  are disposed around the pipe part  36   a  in the manner of being separated from the acoustic sensor  50   b   1  by 120 degrees. For example, it is considered that the deposit D may be unevenly deposited in the upper portion in the pipe part  36   a.  In this case, the degree of non-uniform deposition of the deposit D can be evaluated using the acoustic sensor  50   b   2  and the acoustic sensor  50   b   3 . 
     According to the semiconductor manufacturing apparatus and the control method of the semiconductor manufacturing apparatus according to the embodiment, it is possible to provide the semiconductor manufacturing apparatus and the control method of the semiconductor manufacturing apparatus that are capable of checking the clogging of the pipe without stopping. 
     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 disclosure. 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 disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure.