Patent Publication Number: US-2023160768-A1

Title: Differential pressure measuring device and substrate treating facility including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0162686 filed in the Korean Intellectual Property Office on Nov. 23, 2021, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a differential pressure measuring device and a substrate treating facility including the same. 
     BACKGROUND ART 
     Recently, as patterns on substrates are miniaturized and highly integrated, the importance of pressure and airflow management inside semiconductor manufacturing facilities is increasing. In particular, in order to prevent the inflow of external particles and effectively discharge the particles generated inside the semiconductor manufacturing facility, it is necessary to manage and adjust the airflow around the semiconductor manufacturing facility. In the case of airflow inside the semiconductor manufacturing facility, the pressure inside the semiconductor manufacturing facility is managed to be higher than the pressure outside the manufacturing facility. In addition, it is possible to adjust the airflow inside the semiconductor manufacturing facility by making the difference in pressure between the inside and the outside of the semiconductor manufacturing facility maintain a constant differential pressure. 
     In monitoring the differential pressure in the facility and controlling the differential pressure, it is important to control the reference pressure, which is the reference for measuring the differential pressure, to be constant. In general, the reference pressure is provided as the measured pressure at a specific location outside the facility. However, a reference pressure measuring port is affected by the downdraft that is continuously supplied from the upper portion of the semiconductor manufacturing line, the transferring means for transferring a transferred object, and the like, in the outside of the facility, and accordingly, there is a problem that a reference pressure hunting phenomenon occurs. 
     In addition, as the reference pressure is hunted, it is impossible to measure the exact differential pressure in the facility, so there is a problem in that it is difficult to manage the differential pressure. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in an effort to provide a differential pressure measuring device capable of accurately measuring a differential pressure and a substrate treating facility including the same. 
     The present invention has also been made in an effort to provide a differential pressure measuring device capable of preventing hunting of a reference pressure, which is a reference for differential pressure measurement, and a substrate treating facility including the same. 
     The present invention has also been made in an effort to provide a differential pressure measuring device capable of minimizing environmental and artificial influences applied to a reference pressure measuring port, and a substrate treating facility including the same. 
     The object of the present invention is not limited thereto, and other objects not mentioned will be clearly understood by those of ordinary skill in the art from the following description. 
     An exemplary embodiment of the present invention provides a substrate treating facility, including: an index module on which a substrate is loaded or unloaded; a treating module for performing a substrate treatment on the substrate loaded into the index module; a buffer chamber disposed between the index module and the treating module; and a differential pressure measuring device for measuring a differential pressure between a pressure at a specific position inside the substrate treating facility and a pressure at a reference position serving as a reference, I which the differential pressure measuring device is provided outside the substrate treating facility. 
     The differential pressure measuring device may include: a first box unit; a second box unit provided above the first box unit; and a third box unit provided inside the second box unit, and the first box unit may include a differential pressure port provided on one side plate among a plurality of side plates and connected to the specific position by a first connection line, and a reference differential pressure port provided on the other side plate among the plurality of side plates and connected to the reference position by a second connection line. 
     Each of the first box unit and the second box unit may have an inner space, and may be provided so the inner space is sealed. 
     The first box unit may include a differential pressure board and a reference differential pressure board provided inside the first box unit, the differential pressure board may be connected to the first connection line to measure a pressure at the specific location, and the reference differential pressure board may be connected to the second connection line to measure the pressure at the reference position. 
     The reference position may be the inside of the third box unit. 
     The third box unit may include a first side plate and a second side plate which are disposed opposite to each other among a plurality of side plates, a first port provided on the first side plate, and a second port provided on the second side plate, the first side plate of the third box unit may be provided to be in contact with one of the plurality of side plates of the second box unit, and the second side plate of the third box unit is provided to be spaced apart from the plurality of side plates of the second box unit, and an inner space of the third box unit may communicate with an inner space of the second box unit by the second port of the second side plate. 
     The first port of the third box unit may be formed through the first side plate and the one side plate of the second box unit, and the first port may be connected to the second connection line. 
     The substrate treating facility may further include a controller, in which the controller may control a difference between the pressure at the specific position measured by the differential pressure board and the pressure at the reference position measured by the reference differential pressure board to be maintained constantly. 
     The pressure at the reference position may be provided as a pressure of the inner space of the third box unit, and a difference between the pressure of the inner space of the second box unit and the pressure of the inner space of the third box unit may be zero. 
     The differential pressure measuring device may be provided above the buffer chamber. 
     The differential pressure measuring device may be provided in a central region of an upper surface of the buffer chamber. 
     The differential pressure measuring device may be provided on a ceiling surface of a space in which the substrate treating facility is provided, and may be provided at a position that does not overlap with a transfer rail that transfers a transferred target. 
     The differential pressure measuring device may be provided at a position where the reference position is not affected by a surrounding environment. 
     Another exemplary embodiment of the present invention provides a differential pressure measuring device for measuring a differential pressure between a first pressure at a specific position and a second pressure at a reference position, the differential pressure measuring device comprising: a first box unit having a sealed inner space; a second box unit disposed above the first box unit and having a sealed inner space; and a third box unit provided inside the second box unit and having an inner space communicating with the inner space of the second box unit, in which the second pressure is a pressure of the inner space of the third box unit. 
     The first box unit may include a differential pressure board provided in the inner space of the first box unit and measuring the first pressure and a reference differential pressure board provided in the inner space of the first box unit and measuring the second pressure. 
     A side plate of the first box unit may include a differential pressure port to which a first connection line connecting the specific position and the differential pressure board is connected, and a reference differential pressure port to which a second connection line connecting the reference position and the reference differential pressure board is connected. 
     The third box unit may include a first side plate and a second side plate which are disposed opposite to each other among a plurality of side plates, a first port provided on the first side plate, and a second port provided on the second side plate, the first side plate of the third box unit may be provided to be in contact with one of the plurality of side plates of the second box unit, and the second side plate of the third box unit is provided to be spaced apart from the plurality of side plates of the second box unit, and the inner space of the third box unit may communicate with the inner space of the second box unit by the second port of the second side plate, and the second connection line may be connected to the first port of the third box unit. 
     A difference between the pressure of the inner space of the second box unit and the pressure of the inner space of the third box unit may be zero. 
     Still another exemplary embodiment of the present invention provides a substrate treating facility, including: an index module for loading or unloading a substrate; a treating module for performing a substrate treatment on the substrate loaded into the index module, and including a plurality of process chambers that perform different treatments on the substrate; a buffer chamber disposed between the index module and the treating module; a differential pressure measuring device disposed above the buffer chamber and for measuring a differential pressure between a pressure inside the process chamber and a pressure at a reference position; and a controller, in which the differential pressure measuring device includes: a first box unit having a sealed inner space; a second box unit disposed above the first box unit and having a sealed inner space; and a third box unit provided inside the second box unit and having an inner space communicating with the inner space of the second box unit, and the pressure at the reference position is the pressure of the inner space of the third box unit. 
     The plurality of process chambers may include a first process chamber in which a liquid treatment is performed on the substrate, and a second process chamber in which a heat treatment is performed on the substrate, and the first box unit may include a first differential pressure board which is provided in the inner space of the first box unit and measures a pressure inside the first process chamber, a second differential pressure board which is provided in the inner space of the first box unit and measures a pressure inside the second process chamber, and a reference differential pressure board which is provided in the inner space of the first box unit and measures a reference pressure, the controller may control a difference between a pressure measured by the first differential pressure board and a reference pressure measured by the reference differential pressure board to be maintained as a first differential pressure, and controls a difference between a pressure measured by the second differential pressure board and a pressure measured by the reference differential pressure board is maintained as a second differential pressure, and the first differential pressure and the second differential pressure may be different. 
     According to the exemplary embodiment of the present invention, it is possible to provide the differential pressure measuring device capable of accurately measuring a differential pressure and the substrate treating facility including the same. 
     In addition, it is possible to prevent hunting of a reference pressure, which is a reference for measuring a differential pressure. 
     In addition, it is possible to minimize the environmental and artificial influences applied to a reference pressure measuring port. 
     The effect of the present invention is not limited to the foregoing effects, and the not-mentioned effects will be clearly understood by those skilled in the art from the present specification and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view schematically illustrating a substrate treating facility according to an exemplary embodiment of the present invention. 
         FIG.  2    is a cross-sectional view of a substrate treating facility illustrating a coating block or a developing block of  FIG.  1   . 
         FIG.  3    is a top plan view of the substrate treating facility of  FIG.  1   . 
         FIG.  4    is a diagram illustrating an example of a hand of a transfer robot provided in a transfer chamber of  FIG.  3   . 
         FIG.  5    is a top plan view schematically illustrating an example of a heat treating chamber of  FIG.  3   . 
         FIG.  6    is a front view of the heat treating chamber of  FIG.  5   . 
         FIG.  7    is a diagram schematically illustrating an example of a liquid treating chamber of  FIG.  3   . 
         FIG.  8    is a perspective view of a differential pressure measuring device according to an exemplary embodiment of the present invention. 
         FIG.  9    is a front view of the differential pressure measuring device of  FIG.  8   . 
         FIG.  10    is an exploded perspective view of the differential pressure measuring device of  FIG.  8   . 
         FIG.  11    is a cross-sectional view of the differential pressure measuring device of  FIG.  8   . 
         FIG.  12    is a diagram schematically illustrating an example of a differential pressure board of  FIG.  11   . 
         FIG.  13    is a cross-sectional view of a differential pressure measuring device according to another exemplary embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an exemplary embodiment of the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. However, the present invention can be variously implemented and is not limited to the following exemplary embodiments. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein is omitted to avoid making the subject matter of the present invention unclear. In addition, the same reference numerals are used throughout the drawings for parts having similar functions and actions. 
     Unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. It will be appreciated that terms “including” and “having” are intended to designate the existence of characteristics, numbers, operations, operations, constituent elements, and components described in the specification or a combination thereof, and do not exclude a possibility of the existence or addition of one or more other characteristics, numbers, operations, operations, constituent elements, and components, or a combination thereof in advance. 
     Singular expressions used herein include plurals expressions unless they have definitely opposite meanings in the context. Accordingly, shapes, sizes, and the like of the elements in the drawing may be exaggerated for clearer description. 
     Terms, such as first and second, are used for describing various constituent elements, but the constituent elements are not limited by the terms. The terms are used only to discriminate one constituent element from another constituent element. For example, without departing from the scope of the invention, a first constituent element may be named as a second constituent element, and similarly a second constituent element may be named as a first constituent element. 
     It should be understood that when one constituent element referred to as being “coupled to” or “connected to” another constituent element, one constituent element can be directly coupled to or connected to the other constituent element, but intervening elements may also be present. In contrast, when one constituent element is “directly coupled to” or “directly connected to” another constituent element, it should be understood that there are no intervening element present. Other expressions describing the relationship between the constituent elements, such as “between ˜” and “just between ˜” or “adjacent to ˜” and “directly adjacent to ˜” should be interpreted similarly. 
     All terms used herein including technical or scientific terms have the same meanings as meanings which are generally understood by those skilled in the art unless they are differently defined. Terms defined in generally used dictionary shall be construed that they have meanings matching those in the context of a related art, and shall not be construed in ideal or excessively formal meanings unless they are clearly defined in the present application. 
     A device of the present exemplary embodiment may be used to perform photo processing on a circular substrate. In particular, the device of the present exemplary embodiment may be connected to an exposure device and used to perform a coating process and a developing process on a substrate. However, the technical spirit of the present invention is not limited thereto, and may be used in various types of processes for supplying a treatment liquid to the substrate while rotating the substrate. Hereinafter, a case in which a wafer is used as a substrate will be described as an example. 
     Hereinafter, an exemplary embodiment of the present invention will be described with reference to  FIGS.  1  to  13   . 
       FIG.  1    is a perspective view schematically illustrating a substrate treating facility according to an exemplary embodiment of the present invention,  FIG.  2    is a cross-sectional view of a substrate treating facility illustrating a coating block or a developing block of  FIG.  1   , and  FIG.  3    is a top plan view of the substrate treating facility of  FIG.  1   . 
     Referring to  FIGS.  1  to  3   , a substrate treating facility  10  according to the exemplary embodiment of the present invention includes an index module  100 , a treating module  300 , and an interface module  400 . According to an example, the index module  100 , the treating module  300 , and the interface module  400  may be sequentially arranged in a line. Hereinafter, a direction in which the index module  100 , the treating module  300 , and the interface module  400  are arranged is referred to as a first direction  12 , and a direction perpendicular to the first direction  12  when viewed from the top is referred to as a second direction  14 , and a direction perpendicular to both the first direction  12  and the second direction  14  is referred to as a third direction  16 . 
     The index module  100  may transfer a substrate W to the treating module  300  from a vessel F in which the substrate W is accommodated, and receive the completely treated substrate W into the vessel F. A longitudinal direction of the index module  100  may be provided in the second direction  14 . The index module  100  may include a load port  110  and an index frame  130 . The load port  110  may be coupled to the index frame  130 . The load port  110  may be coupled to one side of the index frame  130 . The load port  110  may be disposed on the opposite side of the treating module  300  with respect to the index frame  130 . The vessel F in which the plurality of substrates W are accommodated may be placed in the load port  110 . The load port  110  may include a plurality of load ports  110 . The plurality of load ports  110  may be disposed along the second direction  14 . The plurality of load ports  110  may be disposed along the longitudinal direction of the index frame  130 . 
     The vessel (F) may be provided as a vessel for sealing. For example, the vessel F may be provided as a Front Open Unified Pod (FOUP). The vessel F may be placed on the load port  110  by a transfer means (not illustrated), such as an OverHead Transfer (OHT), an overhead conveyor, or an automatic guided vehicle, or an operator. 
     The index frame  130  may transfer the substrate W between the vessel F placed on the load port  110  and the treating module  300 . The index frame  130  may include an index robot  132  and a guide rail  134 . The guide rail  134  may be provided inside the index frame  130 , and a longitudinal direction thereof may be provided in the second direction  14 . The longitudinal direction of the guide rail  134  may be the same as the longitudinal direction of the index frame  130 . The index robot  132  may be provided movably on the guide rail  134 . For example, the index robot  132  may move in the second direction along the guide rail  134 . The index robot  132  may include a hand  1321  on which the substrate W is placed. The hand  1321  may move forward and backward based on an axis in the longitudinal direction of the guide rail  134 . In addition, the hand  1321  may be rotated about the third direction  16  as an axis. Also, the hand  1321  may be movable in the third direction  16 . 
     The treating module  300  may perform a coating process and a developing process on the substrate W. The treating module  300  includes a coating block  300   a  and a developing block  300   b.  The coating block  300   a  may perform a coating process on the substrate W. The developing block  300   b  may perform a developing process on the substrate W. The coating block  300   a  may be provided as a plurality of coating blocks  300   a.  The plurality of coating blocks  300   a  may be provided to be stacked on each other. The developing block  300   b  may include a plurality of developing blocks  300   b.  The plurality of developing blocks  300   b  may be provided to be stacked on each other. Also, the coating block  300   a  and the developing block  300   b  may be stacked on each other. For example, the plurality of coating blocks  300   a  and the plurality of developing blocks  300   a  may be stacked. As another example, one coating block  300   a  and one developing block  300   b  may be alternately stacked. Referring to the exemplary embodiment of  FIG.  2   , the coating block  300   a  and the developing block  300   b  may include two coating blocks  300   a  and two developing blocks  300   b,  respectively. Also, the two coating blocks  300   a  may be disposed under the two developing blocks  300   b.    
     The plurality of coating blocks  300   a  may perform the same process as each other, and may be provided in the same structure. Further, the plurality of developing blocks  300   b  may perform the same process and may be provided in the same structure. 
     Referring to  FIG.  3   , the coating block  300   a  may include a heat treating chamber  320 , a transfer chamber  340 , a liquid treating chamber  360 , and a buffer chamber  380 . The heat treating chamber  320  may perform a heat treatment process on the substrate W. The heat treating process may include a cooling process and a heating process. The liquid treating chamber  360  may form a liquid film by supplying a liquid onto the substrate W. The liquid film may be a photoresist film or an antireflection film. The transfer chamber  340  may transfer the substrate W between the heat treating chamber  320  and the liquid treating chamber  360  in the coating block  300   a.    
     The transfer chamber  340  may be provided so that a longitudinal direction thereof is parallel to the first direction  12 . The transfer chamber  340  may include a transfer robot  342  and a guide rail  346 . A guide rail  346  may be provided in the transfer chamber  340 . A longitudinal direction of the guide rail  346  may be provided to be parallel to the first direction  12 . The guide rail  346  may have the same longitudinal direction as the longitudinal direction of the transfer chamber  340 . The transfer robot  342  may transfer a substrate between the heat treating chamber  320 , the liquid treating chamber  360 , and the buffer chamber  380 . The transfer robot  342  may be provided movably on the guide rail  346 . The transfer robot  342  may have a hand  344  on which the substrate W is placed. The hand  344  may move the transfer chamber  340  forward and backward based on an axis in the longitudinal direction of the guide rail  346 . In addition, the hand  344  may be provided to be rotatable about the third direction  16  as an axis. In addition, the hand  344  may be provided to be movable along the third direction  16 . 
       FIG.  4    is a diagram illustrating an example of the hand of the transfer robot provided in the transfer chamber of  FIG.  3   . 
     Referring to  FIG.  4   , the hand  344  of the transfer robot  342  may include a base  3442  and a support protrusion  3444 . The base  3442  may be provided in an annular ring shape in which a portion of the circumference is cut off. The base  3442  may have an inner diameter greater than the diameter of the substrate W. The support protrusion  3444  may protrude inward from the base  3442 . The support protrusion  3444  may include a plurality of support protrusions  3444 . The plurality of support protrusions  3444  may be spaced apart from each other. The plurality of support protrusions  3444  may support an edge region of the substrate W. According to the example, four support protrusions  3444  may be provided at equal intervals. 
     A plurality of heat treating chambers  320  may be provided. The plurality of heat treating chambers  320  may be arranged along the first direction  12 . The plurality of heat treating chambers  320  may be disposed at one side of the transfer chamber  340 . Some of the plurality of heat treating chambers  320  may be provided at a position adjacent to the index module  100 . Hereinafter, these heat treating chambers  320  may be referred to as front heat treating chambers  3202 . Another portion of the plurality of heat treating chambers  320  may be provided at a position adjacent to the interface module  400 . Hereinafter, these heat treating chambers  320  may be referred to as rear heat treating chambers  3204 . A heat treatment process may be performed on the substrate W in the front heat treating chamber  3202  and the rear heat treating chamber  3204 . The front heat treating chamber  3202  and the rear heat treating chamber  3204  may be provided in the same structure. 
       FIG.  5    is a top plan view schematically illustrating an example of the heat treating chamber of  FIG.  3   , and  FIG.  6    is a front view of the heat treating chamber of  FIG.  5   . Referring to  FIGS.  5  and  6   , the heat treating chamber  320  may include a housing  321 , a cooling unit  322 , a heating unit  323 , and a transfer plate  324 . 
     The housing  321  may be provided in the shape of a substantially rectangular parallelepiped. An entrance (not illustrated) through which the substrate W enters and exits may be formed on a sidewall of the housing  321 . The entrance may remain open. Optionally, a door (not illustrated) for opening and closing the entrance may be provided. The cooling unit  322 , the heating unit  323 , and the transfer plate  324  may be provided in the housing  321 . The cooling unit  322  and the heating unit  323  may be provided side by side along the second direction  14 . According to the example, the cooling unit  3220  may be located closer to the transfer chamber  3400  than the heating unit  323 . 
     The cooling unit  322  may include a cooling plate  3222 . The cooling plate  3222  may have a generally circular shape when viewed from the top. A cooling member  3224  may be provided on the cooling plate  3222 . According to the example, the cooling member  3224  is formed inside the cooling plate  3222  and may be provided as a flow path through which the cooling fluid flows. 
     The heating unit  323  may include a heating plate  3231 , a heater  3233 , and a cover  3235 . The heating plate  3231  may have a generally circular shape when viewed from the top. The heating plate  3231  may have a larger diameter than the substrate W. The heater  3233  may be installed on the heating plate  3231 . The heater  3233  may be provided as a heating resistor to which current is applied. Lift pins  3239  drivable in the vertical direction along the third direction  16  may be provided on the heating plate  3231 . The lift pin  3239  may receive the substrate W from an external transfer means and put the substrate W down on the heating plate  3231  or lift the substrate W from the heating plate  3231  and transfer the substrate W it to the transfer means outside the heating unit  3231 . According to the example, three lift pins  3239  may be provided. The cover  3235  may have a space with an open lower portion therein. The cover  3235  is positioned on the heating plate  3231  and may be moved in the vertical direction by the driver  3237 . When the cover  3235  is in contact with the heating plate  3231 , a space surrounded by the cover  3235  and the heating plate  3231  may be provided as a heating space for heating the substrate W. 
     The transfer plate  324  is provided in a substantially circular plate shape, and may have a diameter corresponding to that of the substrate W. A slit-shaped guide groove  3242  may be formed in the transfer plate  340 . The guide groove  3242  may be formed to extend from the end of the transfer plate  340  to the inside of the transfer plate  340 . A longitudinal direction of the guide groove  3242  may be formed in the second direction  14 . The guide groove  3242  may include a plurality of guide grooves  3242 . The plurality of guide grooves  3242  may be spaced apart from each other in the first direction  12 . The guide groove  3242  may prevent the transfer plate  324  and the lift pins  3239  from interfering with each other when the substrate W is transferred between the transfer plate  340  and the heating unit  323 . 
     A notch  3244  may be formed at an edge of the transfer plate  324 . The notch  3244  may have a shape corresponding to a protrusion  3444  formed on the hand  342  of the transfer robot  344 . Also, the notch  3244  may be provided in a number corresponding to the number of protrusions  3444  formed on the hand  344 . Also, the notch  3244  may be formed at a position corresponding to that of the protrusion  3444  formed on the hand  344 . The substrate W may be transferred between the hand  344  and the transfer plate  340  at the location where the hand  344  and the transfer plate  340  are aligned in the vertical direction. The notch  3244  may include a plurality of notches  3244 . The plurality of notches  3244  may be disposed to be spaced apart from each other along the edge of the transfer plate  324 . The plurality of notches  3244  may be formed at positions where the plurality of notches  3244  does not overlap the guide groove  3242 . For example, one guide groove  3242  may be formed between two notches  3244 . For example, one notch  3244  may be formed between two guide grooves  3242 . 
     The heat treating chamber  320  may include a guide rail  3246  provided therein. A longitudinal direction of the guide rail  3246  may have the second direction  14 . The transfer plate  340  may be mounted onto the guide rail  3246 . The transfer plate  340  may be moved along the guide rail  3246  by the driver  3288 . The transfer plate  340  may transfer the substrate W between the cooling unit  322  and the heating unit  323  while moving along the guide rail  3246 . The transfer plate  340  may move an upper region of the cooling plate  3222  and an upper region of the heating plate  3231  along the guide rail  3246 . 
     The heating of the substrate W may be performed in the state where the substrate W is directly placed on the heating plate  3231 , and the cooling of the substrate W may be performed in the state where the transfer plate  324  on which the substrate W is placed is in contact with the cooling plate  3222 . The transfer plate  324  may be made of a material having high transmittance so that the heat is transmitted well between the cooling plate  3222  and the substrate W. According to the example, the transfer plate  324  may be made of a metal material. 
     The heating units  323  provided in some of the heat treating chambers  320  may supply a gas while heating the substrate W to improve the adhesion rate of the photoresist to the substrate W. According to an example, the gas may be hexamethyldisilane (HMDS) gas. 
     The liquid treating chambers  360  may be provided in plural. Some of the liquid treating chambers  360  may be provided to be stacked with each other. The plurality of liquid treating chambers  360  may be disposed at one side of the transfer chamber  340 . The plurality of liquid treating chambers  360  may be arranged side by side in the first direction  12 . Some of the plurality of liquid treating chambers  360  may be provided at positions adjacent to the index module  100 . Hereinafter, the liquid treating chambers are called the front liquid treating chambers  3602 . Another some of the plurality of liquid treating chambers  360  may be provided at positions adjacent to the interface module  400 . Hereinafter, the liquid treating chambers are called the rear liquid treating chambers  3604 . 
     The front liquid treating chamber  3602  may coat a first liquid on the substrate W, and the rear liquid treating chamber  3602  may coat a second liquid on the substrate W. The first liquid and the second liquid may be different types of liquid. According to the exemplary embodiment, the first liquid may be provided as an antireflection film and the second liquid may be provided as a photoresist. The photoresist may be coated onto the substrate W coated with the antireflection film. Optionally, the first liquid may be a photoresist, and the second liquid may be an antireflection film. In this case, the antireflection film may be applied onto the substrate W coated with the photoresist. Optionally, the first liquid and the second liquid are the same type of liquid, and both the first liquid and the second liquid may be the photoresist. 
       FIG.  7    is a diagram schematically illustrating an example of the liquid treating chamber of  FIG.  3   . Referring to  FIG.  7   , the liquid treating chamber  360  may include a housing  361 , a cup  363 , a substrate support unit  365 , and a liquid supply unit  369 . The housing  361  may be provided in the shape of a substantially rectangular parallelepiped. An entrance (not illustrated) through which the substrate W enters and exits may be formed on a sidewall of the housing  361 . The entrance may be opened/closed by a door (not illustrated). The cup  363 , the substrate support unit  365 , and the liquid supply unit  369  may be provided inside the housing  361 . A fan filter unit  367  forming a downdraft within the housing  3620  may be provided in an upper wall of the housing  361 . The cup  363  may have a treatment space with an open top. The support unit  365  is disposed in the treatment space and may support the substrate W. The support unit  365  may be provided so that the substrate W is rotatable during the liquid treatment. The liquid supply unit  369  may supply a liquid to the substrate W supported by the support unit  365 . 
     The buffer chambers  380  may be provided in plural. Some of the plurality of buffer chambers  380  may be disposed between the index module  100  and the transfer chamber  340 . Hereinafter, the foregoing buffer chambers  380  are referred to as front buffers  3802 . The front buffers  3802  may be provided in plural, and may be disposed to be stacked with each other in the vertical direction. Another some of the plurality of buffer chambers  380  may be disposed between the transfer chamber  340  and the interface module  400 . Hereinafter, the buffer chambers  380  may be referred to as rear buffers  3804 . The rear buffers  3804  may be provided in plural, and may be disposed to be stacked with each other in the vertical direction. The front buffers  3802  and the rear buffers  3804  may temporarily store the plurality of substrates W, respectively. The substrate stored in the front buffer  3802  may be loaded or unloaded by the index robot  132  and the transfer  342 . The substrate W stored in the rear buffer  3804  may be loaded or unloaded by the transfer robot  342  and the first robot  442 . Each of the buffer chambers  3802  and  3804  may temporarily store the substrate before and after the process processing of the substrate, and may be provided as a cooling unit (not illustrated) capable of cooling the substrate. The cooling unit may be provided so that a plurality of Wafer Cooling Plates (WCPs) is stacked in the vertical direction. The cooling units may be provided in plural to be positioned to correspond to the coating modules  300   a  and the developing modules  300   b,  respectively. 
     The developing block  300   b  may include a heat treating chamber  320 , a transfer chamber  340 , and a liquid treating chamber  360 . The heat treating chamber  320  and the transfer chamber  340  of the developing block  300   b  are provided in the structure and the disposition substantially similar to those of the heat treating chamber  320  and the transfer chamber  340  of the coating block  300   a,  so that the description thereof will be omitted. 
     In the developing block  300   b,  the liquid treating chambers  360  may be provided as developing chambers for developing the substrate by supplying the same developing liquid. 
     Referring back to  FIGS.  1  to  3   , the interface module  400  may connect the treating module  300  to an external exposing device  500 . The interface module  400  may include an interface frame  410 , an additional process chamber  420 , an interface buffer  430 , and a transfer member  440 . 
     A fan filter unit for forming a descending airflow therein may be provided at an upper end of the interface frame  410 . The additional process chamber  420 , the interface buffer  430 , and the transfer member  440  may be disposed inside the interface frame  410 . The additional treating chamber  420  may perform a predetermined additional process before the substrate W, which has been completely processed in the coating block  300   a,  is loaded into the exposing device  500 . Optionally, the additional treating chamber  420  may perform a predetermined additional process before the substrate W, which has been completely processed in the exposing device  500 , is loaded into the developing block  300   b.  According to one example, the additional process is an edge exposure process of exposing an edge region of the substrate W, a top surface cleaning process of cleaning the upper surface of the substrate W, or a lower surface cleaning process of cleaning the lower surface of the substrate W. A plurality of additional process chambers  420  is provided, and may be provided to be stacked on each other. All of the additional process chambers  420  may be provided to perform the same process. Optionally, some of the additional process chambers  420  may be provided to perform different processes. 
     The interface buffer  430  may provide a space in which the substrate W transferred between the coating block  300   a,  the additional process chamber  420 , the exposing device  500 , and the developing block  300   b  temporarily stays during the transfer. A plurality of interface buffers  360  may be provided, and the plurality of interface buffers  360  may be provided to be stacked on each other. 
     According to the example, the additional process chamber  420  may be disposed on one side based on an extended line in the longitudinal direction of the transfer chamber  340  and the interface buffer  440  may be disposed on the other side. 
     The transfer member  440  may transfer the substrate W between the coating block  300   a,  the additional process chamber  420 , the exposing device  500 , and the developing block  300   b.  The transfer member  380  may be provided as one or a plurality of robots. According to the example, the transfer member  440  may include a first robot  442  and a second robot  444 . The first robot  442  may transfer the substrate W between the coating block  300   a,  the additional process chamber  420 , and the interface buffer  430 , and the second robot  444  may transfer the substrate between the interface buffer  430  and the exposing device  500 . According to the example, the transfer member  440  may include a third robot, and the third robot may be provided to transfer the substrate W between the interface buffer  430  and the developing block  300   b.  Each of the first robot  442  and the second robot  444  include a hand on which the substrate W is placed, and the hand may be provided to be movable in a forward and backward directions, rotatable based on an axis parallel to the third direction  16 , and movable in the third direction  16 . 
     All of the hands of the index robot  132 , the first robot  442 , and the second robot  444  may be provided in the same shape as that of the hand  344  of the transfer robot  342 . Optionally, the hand of the robot that directly exchanges the substrate W with the transfer plate  324  of the heat treating chamber  320  may be provided in the same shape as that of the hand  344  of the transfer robot  342 , and the hand of the remaining robot may be provided in a different shape. 
     According to the exemplary embodiment, the index robot  132  is provided to directly exchange the substrate W with the heating unit  323  of the front heat treating chamber  323  provided to the coating block  300   a.    
     Further, the transfer robots  342  provided to the coating block  300   a  and the developing block  300   b  may be provided to directly exchange the substrate W with the transfer plate  324  located in the heat treating chamber  320 . 
     The substrate treating facility  10  may include a differential pressure measuring device  600 . Hereinafter, the differential pressure measuring device  600  according to an exemplary embodiment of the present invention will be described in detail with reference to the drawings. 
       FIG.  8    is a perspective view of a differential pressure measuring device according to an exemplary embodiment of the present invention,  FIG.  9    is a front view of the differential pressure measuring device of  FIG.  8   ,  FIG.  11    is a cross-sectional view of the differential pressure measuring device of  FIG.  8   , and  FIG.  12    is a diagram schematically illustrating an example of a differential pressure board of  FIG.  11   . 
     The differential pressure measuring device  600  may measure a differential pressure between a pressure at a specific position inside the substrate treating facility  10  and a pressure at a reference position serving as a reference. For example, the differential pressure measuring device  600  may measure a differential pressure between a pressure at a specific position inside the index module  100 , the treating module  300 , or the interface module  400  provided to the substrate treating facility  10 , and a pressure at a reference position. For example, the differential pressure measuring device  600  may measure the differential pressure between the pressure inside the index frame  130  and the pressure at the reference position. For example, the differential pressure measuring device  600  may measure a differential pressure between the pressure in each chamber (the heat treating chamber  320 , the transfer chamber  340 , and the liquid treating chamber  360 ) provided to the treating module  300  and the pressure at the reference position. The controller  700  may monitor the differential pressure measured by the differential pressure measuring device  600  and control the differential pressure value to be maintained constantly. 
     Referring to  FIGS.  1  to  3   , the differential pressure measuring device  600  may be provided outside the substrate treating facility  10 . The differential pressure measuring device  600  may be provided at a position where the reference position for measuring the reference pressure is not affected by the surrounding environment or the influence by the surrounding environment is minimized The differential pressure measuring device  600  may be provided on a ceiling surface of a space in which the substrate treating facility  10  is provided, and may be provided at a position that does not overlap with a transfer rail (not illustrated) for transferring a transferred target. As an example, the differential pressure measuring device  600  may be provided at a location that does not overlap a driving path on which a transfer means, such as an overhead transfer (OHT), an overhead conveyor, or an automatic guided vehicle, travels. 
     The differential pressure measuring device  600  may be provided above the substrate treating facility  10 . For example, the differential pressure measuring device  600  may be installed on the upper surface of the substrate treating facility  10 . The differential pressure measuring device  600  may be provided above the buffer chamber  380  in the upper portion of the substrate treating facility  10 . The differential pressure measuring device  600  may be provided on the upper surface of the front buffer chamber  3802 . The differential pressure measuring device  600  may be provided in a central region of the upper surface of the front buffer chamber  3802 . However, the present invention is not limited thereto, and the differential pressure measuring device  600  may be installed anywhere on the upper portion of the substrate treating stand  10  where the influence by the surrounding environment is minimal Through this, when the reference pressure, which is the reference for measuring the differential pressure, is measured, the influence from the surrounding environment may be minimized, so that the reference pressure may be maintained constantly. Through this, it is possible to more accurately measure and monitor the differential pressure, and it is possible to minimize the differential pressure hunting phenomenon. 
     Referring to  FIGS.  8  to  12   , the differential pressure measuring device  600  may include a first box unit  610 , a second box unit  630 , and a third box unit  650 . 
     Referring to  FIGS.  8  and  9   , the first box unit  610  may be provided below the second and third box units  630  and  650 . The first box unit  610  is provided in a rectangular cross-section, and may have an inner space  611  therein. Referring to  FIG.  10   , the first box unit  610  may include an upper plate  6111 , a lower plate  6112  disposed opposite to the upper plate  6111 , and a plurality of side plates  6113 ,  6114 ,  6115 , and  6116  connecting the upper plate  6111  and the lower plate  6112 . The plurality of side plates  6113 ,  6114 ,  6115 , and  6116  may include first to fourth side plates  6113 ,  6114 ,  6115  and  6116  adjacent to each other. The inner space  611  of the first box unit  610  may be a space formed by a combination of the upper plate  6111 , the lower plate  6112 , and the first to fourth side plates  6113 ,  6114 ,  6115 , and  6116 . 
     The inner space  611  of the first box unit  610  may be provided as a space sealed by the upper plate  6111 , the lower plate  6112 , and the first to fourth side plates  6113 ,  6114 ,  6115 , and  6116 . 
     Referring to  FIG.  11   , the first box unit  610  may include a reference differential pressure port  612  and a differential pressure port  613 . (a) of  FIG.  11    is a cross-sectional view of the first box unit  610 , and (b) of  FIG.  11    is a cross-sectional view of the second and third box units  630  and  650 . 
     The differential pressure port  613  may be provided on any one of the plurality of side plates of the first box unit  610 . The differential pressure port  613  may include a plurality of differential pressure ports  613 . The plurality of differential pressure ports  613  may be provided on any one of the plurality of side plates. The plurality of differential pressure ports  613  may be spaced apart from each other. However, the present invention is not limited thereto and the plurality of differential pressure ports  613  may be provided at a position where connection with a connection line to be described later is easy. For example, the plurality of differential pressure ports  613  may be provided on different side plates. The differential pressure port  613  may be a port to which a first connection line  661  to be described later is coupled. The differential pressure port  613  may be provided as a hole penetrating the side plate. A first connection line  661  may pass through the differential pressure port  613 . The plurality of differential pressure ports  613  may be provided in a number corresponding to the number of differential pressure boards  615  provided inside the first box unit  610 . 
     The reference differential pressure port  612  may be provided on any one of the plurality of side plates. The reference differential pressure port  612  may be coupled to a second connection line  662  to be described later. The reference differential pressure port  612  may be a connection passage between the reference position connected through the second connection line  662  and the reference differential pressure board  614 . The reference differential pressure port  612  may include one reference differential pressure port  612 . The reference differential pressure port  612  may be provided on a side plate different from the side plate on which the differential pressure port  613  is provided. Alternatively, the reference differential pressure port  612  may be provided on the same side plate on which the differential pressure port  613  is provided. That is, the reference differential pressure port  612  may be provided at a position where the second connection line  662  is easy to connect the reference differential pressure board  612  and the reference position. 
     The first box unit  610  may include the reference differential pressure board  614  and a differential pressure board  615  provided in the inner space  611 . The reference differential pressure board  614  and the differential pressure board  615  may be provided as sensors. The reference differential pressure board  614  and the differential pressure board  615  may be provided as pressure measuring sensors that measure pressure in a specific space. For example, the reference differential pressure board  614  and the differential pressure board  615  may be provided as room pressure measuring sensors. 
     The differential pressure board  615  may include a plurality of differential pressure boards  615 . Each of the plurality of differential pressure boards  615  may be connected one-to-one with a plurality of differential pressure ports  613  to be described later. In addition, each of the plurality of differential pressure boards  615  may be connected one-to-one with a chamber of which the differential pressure is to be measured in the treating module  300 . The differential pressure board  615  may be connected to the first connection line  661 . One end of the first connection line  661  may be connected to the differential pressure board  615 , and the other end may be provided in a space in which pressure is to be measured. In this case, the space in which the pressure is to be measured may be a treatment space of any one of a plurality of chambers provided in the treating module  300 . For example, the other end of the first connection line  661  may be connected to any one of the treatment space of the heat treating chamber  320 , the inner space of the transfer chamber  340 , and the treating space of the liquid treating chamber  360 . In addition, a sensor may be coupled to the other end of the first connection line  661 , and through this, the differential pressure board  515  may measure the pressure of the space in which the other end of the first connection line  661  is located. 
     The differential pressure board  615  may include a plurality of differential pressure boards  615 . The plurality of differential pressure boards  615  may be provided in the inner space  611  of the first box unit  610 . The plurality of differential pressure boards  615  may be disposed to be spaced apart from each other inside the first box unit  610 . When a plurality of differential pressure boards  615  are provided, a plurality of first connection lines  661  may also be provided to be connected to the plurality of differential pressure boards  615 , respectively. For example, when the plurality of differential pressure boards  615  include a first differential pressure board, a second differential pressure board, and a third differential pressure board, the first connection line  661  may include a first-1 connection line connected to the first differential pressure board, a first-2 connection line connected to the second differential pressure board, and a first-3 connection line connected to the third differential pressure board. In this case, the first-1 connection line, the first-2 connection line, and the first-3 connection line may be connected to different chambers. For example, the first-1 connection line may be connected to any one of the plurality of liquid treating chambers  360  provided in the coating block  30   a  of the substrate treating facility  10 , the first-2 connection line may be connected to another one of the plurality of liquid treating chambers  360  provided in the coating block  30   a  of the substrate treating facility  10 , and the first-3 connection line may be connected to another one of the plurality of liquid treating chambers  360  provided in the coating block  30   a  of the substrate treating facility  10 . In this case, the first differential pressure board may measure the pressure of the treating space of any one of the plurality of liquid treating chambers  360 , the second differential pressure board may measure the pressure of the treating space of another one of the plurality of liquid treating chambers  360 , and the third differential pressure board may measure the pressure of the treating space of another one of the plurality of liquid treating chambers  360 . In addition, as an example, the first-1 connection line may be connected to any one of the plurality of liquid treating chambers  360  provided in the coating block  30   a  of the substrate treating facility  10 , the first-2 connection line may be connected to another one of the plurality of heat treating chambers  320  provided in the coating block  30   a  of the substrate treating facility  10 , and the first-3 connection line may be connected to the transfer chamber  340  provided in the coating block  30   a  of the substrate treating facility  10 . In this case, the first differential pressure board may measure the pressure of the treating space of any one of the plurality of liquid treating chambers  360 , the second differential pressure board may measure the pressure of the treating space of any one of the plurality of heat treating chambers  320 , and the third differential pressure board may measure the pressure of the treating space of the transfer chamber  340 . For example, the first-1 connection line may be connected to any one of the plurality of chambers provided in the coating block  30   a  of the substrate treating facility  10 , and the first-2 connection line may be connected to any one of the plurality of chambers provided in the developing block  30   b  of the substrate treating facility  10 . In this case, the first differential pressure board may measure the pressure of the treating space of any one of the plurality of chambers provided in the coating block  30   a,  and the second differential pressure board may measure the pressure of the treating space of any one of the plurality of chambers provided in the developing block  30   b.  That is, the differential pressure board  615  is provided in a number corresponding to the number of chambers in which the internal pressure is to be measured, and may be connected to each chamber one-to-one by the first connection line  661 . 
     The reference differential pressure board  614  is provided in the inner space  611  of the first box unit  610 . The reference differential pressure board  614  is disposed to be spaced apart from the differential pressure board  615 . The reference differential pressure board  614  may measure the pressure at the reference position. The reference differential pressure board  614  may be connected to a space for measuring the reference pressure by the second connection line  662 . The reference differential pressure board  614  provides a reference pressure for measuring the differential pressure. The reference pressure may be the pressure of the inner space of the third box unit  650  to be described later. The reference differential pressure board  614  may be connected to the inner space of the third box unit  650  by a second connection line  662 . One end of the second connection line  662  may be connected to the reference differential pressure board  614 , and the other end may be connected to the inner space of the third box unit  650 . 
       FIG.  12    illustrates the differential pressure board. The differential pressure board illustrated in  FIG.  12    may be the reference differential pressure board  614  and/or the differential pressure board  615 . That is, the differential pressure board  615  and the reference differential pressure mode  614  may be provided in the same structure. Hereinafter, the differential pressure board  615  will be described as a reference. The differential pressure board  615  may include an air-in port  6131  for receiving an airflow in a space to measure pressure. The air-in port  6131  may be connected to the first connection line  661 . An in-port of the reference differential pressure board  614  may be connected to the second connection line  662 . The differential pressure board  615  may measure the pressure of the airflow introduced through the air-in port  6131 . The differential pressure board  615  may include an air-out port  6132 . However, the air-out port  6132  may be omitted, or the air-out port  6132  may be maintained in a closed state as illustrated in  FIG.  11   . 
     The second box unit  630  may be provided on the first box unit  610 . The second box unit  630  may have a rectangular cross-section. The cross-sectional area of the second box unit  630  may be smaller than the cross-sectional area of the first box unit  650 . The cross-sectional area of the second box unit  630  may be greater than the cross-sectional area of the third box unit  650 . The second box unit  630  may have an inner space  631 . The third box unit  650  may be accommodated in the inner space  631  of the second box unit  630 . The second box unit  630  may include an upper plate  6311 , a lower plate  6312  disposed opposite to the upper plate  6311 , and a plurality of side plates connecting the upper plate  6311  and the lower plate  6312 . The plurality of side plates may include first to fourth side plates  6313 ,  6314 ,  6315 , and  6316  which are adjacent to each other. The inner space  631  of the second box unit  630  may be provided as a space sealed by the upper plate  6311 , the lower plate  6312 , and the plurality of side plates  6313 ,  6314 ,  6315 , and  6316 . The first side plate  6313  of the second box unit  630  may be in contact with the first side plate  6513  of the third box unit  650  to be described later. The third side plate  6315  of the second box unit  630  may be spaced apart from the second side plate  6514  of the third box unit  650  to be described later. 
     The second box unit  640  may include a hole  632 . The hole  632  may be formed in the first side plate  6313 . The hole  632  may be connected to a first port  652  of the third box unit  650  to be described later. The first port  652  of the third box unit  650  to be described later may be disposed in the hole  632 . The hole  632  is formed at a position corresponding to the first port  652  of the third box unit  650  to be described later, and may communicate with the first port  652 . Through this, the second connection line  662  may be connected to the hole  632 . The second connection line  662  may be connected to the first port  652  through the hole  632 . 
     A port  633  may be provided on the second side plate  6314  and the fourth side plate  6316  which are disposed opposite to each other among the plurality of side plates of the second box unit  640 . The port  633  may include a plurality of ports  633 . The plurality of ports  633  may be maintained in a closed state. However, when it is necessary to adjust the pressure of the inner space  631  of the second box unit  630 , the plurality of ports  633  may be selectively switched to an open state. An opening/closing device may be provided in the plurality of ports  633 . 
     The third box unit  650  may be provided in the second box unit  630 . The third box unit  650  may have a rectangular cross-section. The third box unit  650  may have an inner space  651 . The third box unit  650  may include an upper plate  6511 , a lower plate  6512  disposed opposite to the upper plate  6511 , and a plurality of side plates connecting the upper plate  6511  and the lower plate  6512 . The inner space  651  may be a space defined by the upper plate  6511 , the lower plate  6512 , and the plurality of side plates. The plurality of side plates may include a first side plate  6513  that is in contact with the first side plate  6313  of the second box unit  630 , a second side plate  6514  disposed on the opposite side of the first side plate  6513 , and a third side plate  6515  and a fourth side plate  6516  connecting the first side plate  6513  and the second side plate  6514 . The first side plate  6513  may be in contact with the first side plate  6313  of the second box unit  630 . The second side plate  6514  may face the third side plate  6315  of the second box unit  630 . The second side plate  6514  may be spaced apart from the third side plate  6315  of the second box unit  630 . The third side plate  6515  may face the second side plate  6314  of the second box unit  630 . The third side plate  6515  may be spaced apart from the second side plate  6314  of the second box unit  630 . The fourth side plate  6516  may face the fourth side plate  6316  of the second box unit  630 . The fourth side plate  6516  may be spaced apart from the fourth side plate  6316  of the second box unit  630 . 
     The third box unit  650  may include a first port  652 . The first port  652  may be provided on the first side plate  6513  of the third box unit  650 . The first port  652  may communicate with the hole  632  of the second box unit  630 . The first port  652  may be formed at a position corresponding to the hole  632  of the two-box unit  630 . The first port  652  may be connected to the other end of the second connection line  662 . 
     The third box unit  650  may include a second port  653 . The second port  653  may be disposed opposite to the first port  652 . The second port  653  may be formed on the second side plate  6514 . The second port  653  may be provided as a through hole passing through the second side plate  6514 . The inner space  651  of the third box unit  650  may communicate with the inner space  631  of the second box unit  630  by the second port  653 . Through this, the pressure of the inner space  651  of the third box unit  650  may be provided as a pressure corresponding to the pressure of the inner space  631  of the second box unit  630 . 
     The third box unit  650  may be provided as a space for measuring the reference pressure for measuring the differential pressure. The reference pressure measured by the reference differential pressure board  614  may be the pressure of the inner space  651  of the third box unit  650 . The pressure of the inner space  651  of the third box unit  650  may be provided as atmospheric pressure. A pressure difference between the pressure of the inner space  631  of the second box unit  630  and the pressure of the inner space  650  of the third box unit  650  may be zero. 
     The third box unit  650 , which is a space for measuring the reference pressure, is accommodated in the second box unit  630 , thereby minimizing the influence of the surrounding environment. Through this, it is possible to prevent a pressure hunting phenomenon in which the reference pressure is constantly fluctuated. By preventing the hunting phenomenon of the reference pressure, which is the reference of the differential pressure, accurate differential pressure monitoring and control of the differential pressure may be possible. 
     The substrate treating facility  10  may include a controller  700 . The controller  700  may control the substrate treating facility  10 . For example, the controller  700  may control components of the substrate treating facility  10 . For example, the controller  700  may control each configuration of the substrate treating facility  10  so that the differential pressure measured by the differential pressure measuring device  600  maintains a constant value. Also, the controller  700  may control each process in which the substrate W is treated in the substrate treating facility  10 . 
     Further, the controller  700  may include a process controller formed of a microprocessor (computer) that executes the control of the substrate treating facility  10 , a user interface formed of a keyboard in which an operator performs a command input operation or the like in order to manage the substrate treating facility  10 , a display for visualizing and displaying an operation situation of the substrate treating facility  10 , and the like, and a storage unit storing a control program for executing the process executed in the substrate treating facility  10  under the control of the process controller or a program, that is, a treatment recipe, for executing the process in each component according to various data and treatment conditions. Further, the user interface and the storage unit may be connected to the process controller. The processing recipe may be stored in a storage medium in the storage unit, and the storage medium may be a hard disk, and may also be a portable disk, such as a CD-ROM or a DVD, or a semiconductor memory, such as a flash memory. 
     The controller  700  may receive the respective pressures measured from the reference differential pressure board  614  and the differential pressure board  615 . In this case, the pressure measured by the reference differential pressure board  614  may be referred to as a reference pressure. The controller  700  may calculate a differential pressure between the reference pressure measured by the reference differential pressure board  614  and the pressure measured by the differential pressure board  615 . The controller  700  may monitor and control the differential pressure between the reference pressure measured by the reference differential pressure board  614  and the pressure measured by the differential pressure board  615 . For example, when the process result is changed due to the loss of exhaust pressure in the liquid treating chamber  360  in which the coating process is performed (for example, change in the thickness (thickness, THK) of the coated film, change in the degree of Edge Bead Removal (EBR)), the internal pressure of the liquid treating chamber  360  is increased, so that the differential pressure value is also increased. In this case, the controller  700  increases the pressure in the area of the transfer chamber  340  connected to the liquid treating chamber  360  in which the coating process is performed to control the amount of airflow blown into the liquid treating chamber  360  in which the coating process to be changed. Through this, the differential pressure may be controlled by adjusting the pressure in the treating space of the liquid treating chamber  360  in which the coating process is performed. 
     For example, the controller  700  may monitor a first differential pressure between the pressure measured by the first differential pressure board connected to the treating space of the first treating chamber and the reference pressure measured by the reference differential pressure board  614 . Also, the controller  700  may monitor a second differential pressure between the pressure measured by the second differential pressure board connected to the treating space of the second treating chamber and the reference pressure measured by the reference differential pressure board  614 . In this case, the controller  700  may set and control the first differential pressure and the second differential pressure as different differential pressures. This may vary depending on the type of process performed in each treating chamber. Alternatively, even when the same process is performed in each treating chamber, each chamber may be controlled with a differential pressure according to a process recipe. 
     Hereinafter, a differential pressure measuring device according to another exemplary embodiment of the present invention will be described with reference to the drawings. 
       FIG.  13    is a cross-sectional view of a differential pressure measuring device according to another exemplary embodiment of the present invention. In the differential pressure measuring device  600  according to the exemplary embodiment, the second box unit  630  and the third box unit  650  are disposed on the first box unit  610 , but in a differential pressure measuring device  800  according to another exemplary embodiment, a second box unit  830  may be disposed in an inner space  811  of a first box unit  810 , and the third box unit  850  may be disposed in the inner space  831  of the second box unit  830 . 
     A plurality of differential pressure boards  815  and one reference differential pressure board  814  may be provided in the inner space  811  of the first box unit  810 . A plurality of differential pressure ports  813  connected to a plurality of differential pressure boards  815  and a reference differential pressure port  812  connected to the reference differential pressure board  814  may be provided on one sidewall of the plurality of sidewalls of the first box unit  810 . Each of the plurality of differential pressure boards  815  may be connected to a plurality of differential pressure ports  813  and a plurality of chambers by a plurality of first connection lines  661 . Through this, each of the plurality of differential pressure boards  815  may measure the pressure of the connected treating space. Each of the reference differential pressure boards  814  may be connected to the reference differential pressure port  812  and the third box unit  850  by a second connection line  662 . Through this, the reference differential pressure board  814  may measure the pressure of an inner space  851  of the third box unit  850 . The controller  700  may monitor the differential pressure by measuring a differential pressure between the pressure measured by the differential pressure board  815  and the pressure measured by the reference differential pressure board  814 . Also, the controller  700  may control the measured differential pressure to be maintained constantly. 
     The second box unit  830  may be in contact with one sidewall of the first box unit  810 . As an example, the second box unit  830  may be spaced apart from the sidewall on which the differential pressure port  813  is provided among the plurality of sidewalls of the first box unit  810 , and may be disposed to be in contact with a sidewall disposed opposite to the sidewall on which the differential pressure port  813  is provided among the plurality of sidewalls. The cross-section of the second box unit  830  may be smaller than the cross-section of the first box unit  810 . Accordingly, among the plurality of sidewalls of the second box unit  830 , the remaining sidewalls other than the sidewall that is in contact with the first box unit  810  may be spaced apart from the first box unit  810 . 
     The third box unit  850  may be provided in the inner space  831  of the second box unit  830 . The cross-section of the third box unit  850  may be smaller than the cross-section of the second box unit  830 . The third box unit  850  may be disposed such that two adjacent sidewalls of the plurality of sidewalls are in contact with the second box unit  830 . A first port  852  may be provided on one sidewall that is in contact with the second box unit  830  among the plurality of sidewalls of the third box unit  850 . The first port  852  may be connected to the reference differential pressure board  814  and the second connection line  6620 . The second port  853  may be provided on a sidewall disposed opposite to the sidewall on which the first port  852  is provided among the plurality of sidewalls. The second port  853  may be provided as a hole. Due to the second port  853 , the inner space  851  of the third box unit  850  and the inner space  831  of the second box unit  830  may communicate with each other. 
     The differential pressure measuring device  600  according to the exemplary embodiment of the present invention and the differential pressure measuring device  800  according to another exemplary embodiment have only different structures, and may perform the measurement of the differential pressure, the monitoring of the differential pressure, and the control of the differential pressure in the same method. Accordingly, hereinafter, the duplicate description will be omitted. 
     In order to automatically manage the differential pressure in the substrate treating facility, the space or port that measures the reference pressure, which is the reference of the differential pressure, needs to be minimally affected by the surrounding environment. Otherwise, hunting of the reference pressure occurs due to surrounding environmental factors or artificial factors, making it impossible to accurately measure the differential pressure, which leads to poor differential pressure control and process defects. Therefore, it is important to keep the reference pressure serving as the reference constant. 
     According to the exemplary embodiment of the present invention, it is possible to provide a differential pressure control system capable of generally monitoring the differential pressure in the substrate treating facility and automatically correcting a deviation between modules or chambers. For automatic differential pressure compensation, constant management of the reference pressure serving as a reference is required, and according to the exemplary embodiment of the present invention, as the third box unit providing a space for measuring the reference pressure is provided inside the second box unit, environmental and artificial influences are minimized to prevent pressure hunting. 
     By preventing the hunting of the reference pressure, the reference pressure may be maintained constantly, so the differential pressure state of the entire facility may be reflected in real time, and the change factor may be easily analyzed by monitoring the state change of the facility. 
     The foregoing detailed description illustrates the present invention. Further, the above content illustrates and describes the exemplary embodiment of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, the foregoing content may be modified or corrected within the scope of the concept of the invention disclosed in the present specification, the scope equivalent to that of the disclosure, and/or the scope of the skill or knowledge in the art. The foregoing exemplary embodiment describes the best state for implementing the technical spirit of the present invention, and various changes required in the specific application field and use of the present invention are possible. Accordingly, the detailed description of the invention above is not intended to limit the invention to the disclosed exemplary embodiment. Further, the accompanying claims should be construed to include other exemplary embodiments as well.