Patent Publication Number: US-2023152704-A1

Title: Heat treatment apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Japanese Patent Application No. 2021-188083 filed on Nov. 18, 2021, the entire disclosure of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The exemplary embodiments described herein pertain generally to a heat treatment apparatus. 
     BACKGROUND 
     Patent Document 1 discloses a heating apparatus configured to generate an air flow above a hot plate so as to flow from an inlet for introducing a gas toward an outlet in one direction along the surface of the hot plate.
     Patent Document 1: Japanese Patent Laid-open Publication No. 2001-185471   

     SUMMARY 
     In one exemplary embodiment, a heat treatment apparatus includes a heating unit, a bottom wall, a chamber and a guide unit. The heating unit is configured to support and heat a substrate onto which a processing liquid is supplied. The bottom wall surrounds the substrate supported by the heating unit. The chamber includes a top plate covering the heating unit and side walls provided between the bottom wall and the top plate. The chamber is configured to be detachably attached to a base member provided with the heating unit. The guide unit is configured to guide a movement of the chamber from an installation position, where an inner space of the chamber surrounds the substrate on the heating unit, in a predetermined driving direction along an upper surface of the heating unit. 
     The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, exemplary embodiments, and features described above, further aspects, exemplary embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the detailed description that follows, exemplary embodiments are described as illustrations only since various changes and modifications will become apparent to those skilled in the art from the following detailed description. The use of the same reference numerals in different figures indicates similar or identical items. 
         FIG.  1    is a schematic perspective view illustrating an example of a substrate processing system; 
         FIG.  2    is a schematic side view illustrating a coating and developing apparatus; 
         FIG.  3    is a schematic side view illustrating an example of a heat treatment unit; 
         FIG.  4    is a schematic top view illustrating an example of a chamber and an exhaust unit; 
         FIG.  5    is a schematic bottom view illustrating an example of the chamber and the exhaust unit; 
         FIG.  6 A  and  FIG.  6 B  are schematic side views illustrating an example of the chamber; 
         FIG.  7    is a schematic top view illustrating an example of an inside of the chamber; 
         FIG.  8    is a schematic perspective view illustrating an example of a flow path control unit; 
         FIG.  9    is a schematic top view illustrating an example of the inside of the chamber; 
         FIG.  10 A  and  FIG.  10 B  are schematic side views illustrating an example of a shutter unit; 
         FIG.  11    is a schematic side view illustrating an example of the shutter unit and its neighboring members; 
         FIG.  12    is a schematic perspective view illustrating an example of an inside of the exhaust unit; 
         FIG.  13    is a schematic perspective view illustrating an example of a state where the chamber is mounted; 
         FIG.  14    is a schematic perspective view illustrating an example of a state where the chamber is being separated; 
         FIG.  15 A  and  FIG.  15 B  are schematic side views illustrating an example of attachment and detachment of the chamber; 
         FIG.  16    is a block diagram illustrating an example of a hardware configuration of a control device; 
         FIG.  17    is a flowchart showing an example of a series of processings performed in a heat treatment; 
         FIG.  18 A  and  FIG.  18 B  are schematic diagrams illustrating an example of a heat treatment; 
         FIG.  19    is a schematic diagram illustrating an example of the heat treatment; 
         FIG.  20 A  and  FIG.  20 B  are schematic diagrams illustrating an example of a state where the chamber is being separated; 
         FIG.  21 A  and  FIG.  21 B  are schematic diagrams illustrating an example of a configuration in which the chamber is attached and detached; 
         FIG.  22 A  and  FIG.  22 B  are schematic diagrams illustrating an example of a state where the chamber is being separated; 
         FIG.  23 A  and  FIG.  23 B  are schematic diagrams illustrating an example of a configuration in which the chamber is attached and detached; 
         FIG.  24 A  and  FIG.  24 B  are schematic diagrams illustrating an example of a state where the chamber is being separated; and 
         FIG.  25 A  is a schematic plan view illustrating an example of a base member and  FIG.  25 B  is a schematic diagram illustrating an example of a state where the base member is being separated. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, reference is made to the accompanying drawings, which form a part of the description. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Furthermore, unless otherwise noted, the description of each successive drawing may reference features from one or more of the previous drawings to provide clearer context and a more substantive explanation of the current exemplary embodiment. Still, the exemplary embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other exemplary embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings, may be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein. 
     The following exemplary embodiments are examples for describing the present disclosure, and the present disclosure is not limited thereto. In the following description, same parts or parts having same function will be assigned same reference numerals, and redundant description will be omitted. 
     Hereinafter, one embodiment will be described with reference to the accompanying drawings. In the description, the same components or the components having the same function are designated by like reference numerals, and duplicate description thereof will be omitted. In some drawings, there is shown an orthogonal coordinate system defined by X, Y and Z axes. In the following embodiment, the Z-axis corresponds to a vertical direction and the X-axis and the Y-axis correspond to a horizontal direction. 
     A substrate processing system  1  shown in  FIG.  1    is configured to form a photosensitive film on a workpiece W, expose the photosensitive film and develop the photosensitive film. The workpiece W to be processed is, for example, a substrate, or a substrate on which a film, a circuit or the like is formed by being subjected to a predetermined process. The substrate is, for example, a silicon wafer. The workpiece W (substrate) may be formed into a circular shape. The workpiece W may be a glass substrate, a mask substrate, an FPD (Flat Panel Display), or the like. The photosensitive film is, for example, a resist film. 
     As shown in  FIG.  1    and  FIG.  2   , the substrate processing system  1  includes a coating and developing apparatus  2  (substrate processing apparatus) and an exposure apparatus  3 . The exposure apparatus  3  is configured to expose the resist film (photosensitive film) formed on the workpiece W (substrate). Specifically, the exposure apparatus  3  radiates an energy ray to an exposure target portion of the resist film by immersion exposure or the like. 
     [Coating and Developing Apparatus] 
     The coating and developing apparatus  2  is configured to form the resist film by coating a resist (chemical liquid) on a surface of the workpiece W before an exposure processing is performed by the exposure apparatus  3 , and develop the resist film after the exposure processing. The coating and developing apparatus  2  (heat treatment apparatus) includes a carrier block  4 , a processing block  5 , an interface block  6  and a control device  100 . 
     The carrier block  4  loads the workpiece W into the coating and developing apparatus  2  and unloads the workpiece W from the coating and developing apparatus  2 . For example, the carrier block  4  can support a plurality of carriers C for the workpiece W and incorporates a transfer device A 1  equipped with a transfer arm. Each of the carriers C accommodates, for example, a plurality of circular workpieces W. The transfer device A 1  takes out the workpiece W from the carrier C, passes the same to the processing block  5 , receives the workpiece W from the processing block  5 , and returns the same to the carrier C. The processing block  5  has a plurality of processing modules  11 ,  12 ,  13  and  14 . 
     The processing module  11  incorporates a liquid treatment unit U 1 , a heat treatment unit U 2  and a transfer device A 3  configured to transfer the workpiece W to these units. The processing module  11  forms a lower layer film on the surface of the workpiece W by the liquid treatment unit U 1  and the heat treatment unit U 2 . The liquid treatment unit U 1  coats a processing liquid for formation of the lower layer film on the workpiece W. The heat treatment unit U 2  performs various heat treatments related to the formation of the lower layer film. A plurality of heat treatment units U 2  may be stacked in the processing module  11 . 
     The processing module  12  incorporates a liquid treatment unit U 1 , a heat treatment unit U 2  and a transfer device A 3  configured to transfer the workpiece W to these units. The processing module  12  forms a resist film on the lower layer film by the liquid treatment unit U 1  and the heat treatment unit U 2 . The liquid treatment unit U 1  coats a processing liquid for formation of the resist film on the lower layer film. The heat treatment unit U 2  performs various heat treatments related to the formation of the resist film. A plurality of heat treatment units U 2  may be stacked in the processing module  12 . 
     The processing module  13  incorporates a liquid treatment unit U 1 , a heat treatment unit U 2  and a transfer device A 3  configured to transfer the workpiece W to these units. The processing module  13  forms an upper layer film on the resist film by the liquid treatment unit U 1  and the heat treatment unit U 2 . The liquid treatment unit U 1  coats a processing liquid for formation of the upper layer film on the resist film. The heat treatment unit U 2  performs various heat treatments related to the formation of the upper layer film. A plurality of heat treatment units U 2  may be stacked in the processing module  13 . 
     The processing module  14  incorporates a liquid treatment unit U 1 , a heat treatment unit U 2  and a transfer device A 3  configured to transfer the workpiece W to these units. The processing module  14  performs development of the resist film subjected to the exposure processing and heat treatment related to the development by the liquid treatment unit U 1  and the heat treatment unit U 2 . The liquid treatment unit U 1  forms a resist pattern (develops the resist film) by coating a developer on the surface of the exposed workpiece W and then rinsing the developer with a rinsing liquid. The heat treatment unit U 2  performs various heat treatments related to the development. Specific examples of the heat treatments may include heat treatment before development (PEB: Post Exposure Bake), heat treatment after development (PB: Post Bake), and the like. A plurality of heat treatment units U 2  may be stacked in the processing module  14 . 
     A shelf unit U 10  is provided close to the carrier block  4  inside the processing block  5 . The shelf unit U 10  is partitioned into a plurality of cells arranged in a vertical direction. A transfer device A 7  including an elevating arm is provided in the vicinity of the shelf unit U 10 . The transfer device A 7  raises and lowers the workpiece W between the cells of the shelf unit U 10 . 
     A shelf unit U 11  is provided close to the interface block  6  inside the processing block  5 . The shelf unit U 11  is partitioned into a plurality of cells arranged in the vertical direction. 
     The interface block  6  transfers the workpiece W to and from the exposure apparatus  3 . For example, the interface block  6  incorporates a transfer device A 8  including a transfer arm and is connected to the exposure apparatus  3 . The transfer device A 8  delivers the workpiece W disposed on the shelf unit U 11  to the exposure apparatus  3 . The transfer device A 8  receives the workpiece W from the exposure apparatus  3  and returns the same to the shelf unit U 11 . 
     The control device  100  (controller) is configured to control various devices included in the coating and developing apparatus  2 . The control device  100  controls various devices of the coating and developing apparatus  2  to perform a coating and developing processing in the following procedure. First, the control device  100  controls the transfer device A 1  to transfer the workpiece W in the carrier C to the shelf unit U 10 , and controls the transfer device A 7  to arrange the workpiece W in a cell for the processing module  11 . 
     Subsequently, the control device  100  controls the transfer device A 3  to transfer the workpiece W in the shelf unit U 10  to the liquid treatment unit U 1  and the heat treatment unit U 2  in the processing module  11 . Then, the control device  100  controls the liquid treatment unit U 1  and the heat treatment unit U 2  to form a lower layer film on the surface of the workpiece W. Thereafter, the control device  100  controls the transfer device A 3  to return the workpiece W having the lower layer film formed thereon to the shelf unit U 10 , and controls the transfer device A 7  to arrange the workpiece W in a cell for the processing module  12 . 
     Subsequently, the control device  100  controls the transfer device A 3  to transfer the workpiece W in the shelf unit U 10  to the liquid treatment unit U 1  and the heat treatment unit U 2  in the processing module  12 . Then, the control device  100  controls the liquid treatment unit U 1  and the heat treatment unit U 2  to form a resist film on the lower layer film of the workpiece W. Thereafter, the control device  100  controls the transfer device A 3  to return the workpiece W to the shelf unit U 10 , and controls the transfer device A 7  to arrange the workpiece Win a cell for the processing module  13 . 
     Subsequently, the control device  100  controls the transfer device A 3  to transfer the workpiece W in the shelf unit U 10  to each unit in the processing module  13 . Then, the control device  100  controls the liquid treatment unit U 1  and the heat treatment unit U 2  to form an upper layer film on the resist film of the workpiece W. Thereafter, the control device  100  controls the transfer device A 3  to transfer the workpiece W to the shelf unit U 11 . 
     Subsequently, the control device  100  controls the transfer device A 8  to transfer the workpiece W in the shelf unit U 11  to the exposure apparatus  3 . Then, the control device  100  controls the transfer device A 8  to receive the workpiece W, which has been subjected to the exposure processing, from the exposure apparatus  3  and to arrange the workpiece W in a cell for the processing module  14  in the shelf unit U 11 . 
     Subsequently, the control device  100  controls the transfer device A 3  to transfer the workpiece W in the shelf unit U 11  to each unit in the processing module  14 , and controls the liquid treatment unit U 1  and the heat treatment unit U 2  to perform development of the resist film on the workpiece W. Then, the control device  100  controls the transfer device A 3  to return the workpiece W to the shelf unit U 10 , and controls the transfer device A 7  and the transfer device A 1  to return the same into the carrier C. 
     In the manner as described above, the coating and developing processing for one workpiece W is completed. The control device  100  controls various devices of the coating and developing apparatus  2  to perform the coating and developing processing for each of a subsequent plurality of workpieces W in the same manner as described above. The specific configuration of the coating and developing apparatus  2  is not limited to the example described above. The coating and developing apparatus  2  may have any configuration as long as it includes a unit that performs a heat treatment. 
     [Heat Treatment Unit] 
     Hereinafter, an example of the heat treatment unit U 2  will be described in detail with reference to  FIG.  3    to  FIG.  15 B . The heat treatment unit U 2  (heat treatment apparatus) is configured to perform at least a heating treatment on the workpiece W. As shown in  FIG.  3   , the heat treatment unit U 2  includes, for example, a housing  20 , a transfer unit  30  and a heating treatment unit  40 . 
     (Housing) 
     The housing  20  accommodates a part of a member included in the heat treatment unit U 2 . The housing  20  may extend along a horizontal direction (for example, X-axis direction in the drawings). An inner space of the housing  20  may have a rectangular parallelepiped shape. A carry-in opening  21  through which the workpiece W is carried into the housing  20  is formed in a side wall on one side of the housing  20  in a longitudinal direction. In the following description, the longitudinal direction of the housing  20  is a front-back direction, and a horizontal direction (for example, Y-axis direction in the drawings) orthogonal to the longitudinal direction of the housing  20  is a left-right direction. The carry-in opening  21 , the transfer unit  30  and the heating treatment unit  40  are arranged in this order in the front-back direction. 
     (Transfer Unit) 
     The transfer unit  30  transfers the workpiece W, and performs cooling of the workpiece W. The transfer unit  30  includes, for example, a cooling plate  31 , a connection portion  32 , a driver  33  and a guide rail  34 . The cooling plate  31  supports and cools the workpiece W. A coolant path (not shown) through which a coolant for cooling flows is formed in the cooling plate  31 . The connection portion  32  is connected to the cooling plate  31 . The connection portion  32  is movable along the front-back direction in the housing  20 . A base  24  that partitions the inner space of the housing  20  into an upper portion and a lower portion may be provided in the housing  20 . The cooling plate  31  is located above the base  24 , and the connection portion  32  penetrates through the base  24  in the vertical direction. 
     The driver  33  includes a driving source such as an electric motor, and moves the connection portion  32  along the guide rail  34  extending in the front-back direction. As the connection portion  32  moves, the cooling plate  31  moves along the front-back direction. The driver  33  drives the connection portion  32  in order for the cooling plate  31  to reciprocate between a heating position where the workpiece W is heated in the heating treatment unit  40  and a standby position which is between the heating position and the carry-in opening  21 . The transfer unit  30  (cooling plate  31 ) performs cooling of the workpiece W at the standby position. 
     (Heating Treatment Unit) 
     The heating treatment unit  40  performs heating of the workpiece W at the heating position. The heating treatment unit  40  includes a heating unit  42 , an elevating unit  44 , a chamber  50 , a partition unit  60 , a shutter unit  70 , an exhaust unit  80  and a switching unit  90 . First, the heating treatment unit  40  will be described briefly. The heating unit  42  supports and heats the workpiece Won which a film of a processing liquid has been formed. The elevating unit  44  delivers the workpiece W to and from the cooling plate  31  of the transfer unit  30 . 
     The chamber  50  is provided to surround the workpiece W supported by the heating unit  42 . The chamber  50  is a cover body, and forms a space (hereinafter, referred to as “inner space S”) in which the workpiece W is heated. The partition unit  60  partitions the inner space S of the chamber  50  into a processing space S 1  (first space) where the workpiece W on the heating unit  42  is exposed and a retreat space S 2  (second space) located above the processing space S 1 . The shutter unit  70  is a member configured to open and close a carry-in/out opening  57  for the workpiece W provided in a side wall of the chamber  50 . When the shutter unit  70  closes the carry-in/out opening  57 , the inner space S is formed. While the inner space S is formed, heating of the workpiece W is performed. 
     The exhaust unit  80  discharges a gas from the inner space S of the chamber  50  through a discharge opening  58  located in the vicinity of the heating unit  42 . While the workpiece W is heated, sublimates are generated from the film of the processing liquid formed on the surface of the workpiece W. As the gas is discharged (exhausted) by the exhaust unit  80 , the sublimates generated in the inner space S are collected. The discharge opening  58  includes a first discharge opening  58   a  that is opened to the processing space S 1  and a second discharge opening  58   b  that is opened to the retreat space S 2 . 
     The switching unit  90  switches between a state where a gas is discharged by the exhaust unit  80  through the processing space S 1  (hereinafter, referred to as “first exhaust state”) and a state where a gas is discharged by the exhaust unit  80  through the retreat space S 2  (hereinafter, referred to as “second exhaust state”). In the first exhaust state (first state), the exhaust unit  80  discharges a gas from the processing space S 1  through the first discharge opening  58   a , but does not discharge a gas from the retreat space S 2  through the second discharge opening  58   b . In the second exhaust state (second state), the exhaust unit  80  discharges a gas from the retreat space S 2  through the second discharge opening  58   b , but does not discharge a gas from the processing space S 1  through the first discharge opening  58   a.    
     The standby position where the cooling plate  31  performs cooling of the workpiece W, the shutter unit  70 , the chamber  50  (the heating unit  42 ) and the exhaust unit  80  are arranged in this order in the front-back direction. Most of the exhaust unit  80  may be provided so as to protrude from the housing  20  to the outside. Hereinafter, an example of each member included in the heating treatment unit  40  will be described in detail. 
     &lt;Heating Unit&gt; 
     The heating unit  42  is fixed at a predetermined position in the housing  20 . The heating unit  42  is supported by, for example, a base  25 . The base  25  is fixed at a bottom wall or a side wall of the housing  20 . The base  25  may be connected to the base  24 . The heating unit  42  has a hot plate  43  formed into a circular plate shape. A heater is provided in the hot plate  43 . The hot plate  43  may have a greater diameter than the workpiece W. The workpiece W is supported on an upper surface of the hot plate  43 , and as the temperature of the hot plate  43  increases, the workpiece W is heated. 
     &lt;Elevating Unit&gt; 
     The elevating unit  44  raises and lowers the workpiece W above the hot plate  43 . The elevating unit  44  raises and lowers the workpiece W, for example, between a processing height at which the workpiece W is supported (placed) on the heating unit  42  and a delivery height at which the workpiece W is delivered to and from the transfer unit  30  in an upper portion separated from the heating unit  42 . The elevating unit  44  includes a plurality of elevating pins  45  and an elevation driver  46 . The elevating pins  45  support a lower surface of the workpiece W, and penetrate through the heating unit  42  in the vertical direction. The elevation driver  46  includes a driving source such as an electric motor or a cylinder, and moves the elevating pins  45  in the vertical direction. 
     &lt;Chamber·Bottom Wall&gt; 
     The heating treatment unit  40  has a bottom wall  56  (see  FIG.  5   ). The chamber  50  covers the workpiece W supported by the heating unit  42  and thus forms the inner space S together with the bottom wall  56  and the shutter unit  70 . The inner space S is a space that is closed enough to sufficiently heat the film of the processing liquid formed on the workpiece W. The chamber  50  extends in the front-back direction when viewed from the top as shown in  FIG.  4    or  FIG.  5   . An outer periphery of the chamber  50  may have a rectangular shape with one side open near the standby position and a circular arc shape far from the standby position. The outer periphery of the chamber  50  has a rectangular shape with a circular arc-shaped side, and the circular arc-shaped side protrudes toward the outside. 
     The chamber  50  has a top plate  51 , a side wall  52 , a side wall  53 , a side wall  54  and a side wall  55 . The top plate  51  is a plate-shaped member covering the heating unit  42 . When viewed from the top, an outer periphery of the top plate  51  surrounds an outer periphery of the heating unit  42  (the hot plate  43 ), and the top plate  51  has a greater area than the heating unit  42 . The outer periphery of the top plate  51  forms the outer periphery of the chamber  50 . An upper surface of the inner space S is defined by the top plate  51 . 
     The bottom wall  56  surrounds the workpiece W supported by the heating unit  42 . When viewed from the top, an outer periphery of the bottom wall  56  surrounds the outer periphery of the heating unit  42  (the hot plate  43 ), and the area surrounded by the outer periphery of the bottom wall  56  is greater than the area of the heating unit  42 . When viewed from the top, the outer periphery of the bottom wall  56  may be approximately matched with the outer periphery of the top plate  51 . The top plate  51  may cover the heating unit  42  and the bottom wall  56 . The bottom wall  56  may be connected to a lower end of each side wall of the chamber  50 , or may be integrally formed with the chamber  50 . In the following description, a case where the chamber  50  is integrally formed with the bottom wall  56  will be described as an example. 
     As shown in  FIG.  5   , the bottom wall  56  includes an exposure hole  56   a  through which the heating unit  42  is exposed (see  FIG.  7   ). The exposure hole  56   a  may be smaller than the outer periphery of the heating unit  42 . When viewed from the top, a part of the bottom wall  56  may cover a peripheral portion of the heating unit  42  (see  FIG.  11   ). A lower portion of the bottom wall  56  may be located at the same height position in the vertical direction as an upper portion of the heating unit  42 . A lower surface of the inner space S is defined by the bottom wall  56  and the heating unit  42 . 
     The side wall  52 , the side wall  53 , the side wall  54  and the side wall  55  are provided between the top plate  51  and the bottom wall  56 . Each of the side wall  52 , the side wall  53 , the side wall  54  and the side wall  55  extends downwards from a peripheral portion of the top plate  51 . A part of a side surface of the inner space S is defined by the side wall  52 , the side wall  53 , the side wall  54  and the side wall  55 . The side wall  52  and the side wall  53  are arranged with the heating unit  42  interposed therebetween in the front-back direction. The side wall  54  and the side wall  55  are arranged with the heating unit  42  interposed therebetween in the left-right direction. The side wall  52  is located closer to the shutter unit  70  (or the above-described position) than the side wall  53 . In this case, the shutter unit  70 , the side wall  52  and the side wall  53  are arranged in this order in the front-back direction. 
     The side wall  52  extends along the left-right direction. One end of the side wall  52  in the left-right direction is connected to the side wall  54 , and the other end of the side wall  52  in the left-right direction is connected to the side wall  55 . Each of the side wall  54  and the side wall  55  extends along the front-back direction. In the front-back direction, the length of the side wall  54  may be approximately identical to the length of the side wall  55 . 
     One end of the side wall  53  is connected to the side wall  54 , and the other end thereof is connected to the side wall  55 . When viewed from the top, the side wall  53  has a circular arc shape. In the left-right direction, the length of the side wall  53  may be approximately identical to the length of the side wall  52 . When viewed from the top, the side wall  53  may extend along a circumferential direction around the center of the heating unit  42  (or the center of the hot plate  43 ). A central portion of the side wall  53  in the left-right direction may have a greater thickness in the front-back direction than the other portion. The central portion of the side wall  53  in the left-right direction may protrude in a direction away from the shutter unit  70 . A protrusion of the central portion of the side wall  53  in the left-right direction may be surrounded by a side wall of the housing  20  opposite to the side wall where the carry-in opening  21  is provided. 
     As shown in  FIG.  6 A , the carry-in/out opening  57  for the workpiece W is formed in the side wall  52 . The carry-in/out opening  57  is an opening through which the workpiece W is carried in and carried out. The workpiece W is carried into the chamber  50  through the carry-in/out opening  57 , and the workpiece W is carried out of the chamber  50  through the carry-in/out opening  57 . The carry-in/out opening  57  is formed to allow the cooling plate  31  that supports the workpiece W to pass therethrough. The carry-in/out opening  57  extends along the left-right direction, and the width of the carry-in/out opening  57  is greater than the diameter of the workpiece W. In the vertical direction, the length of the carry-in/out opening  57  may be about half the length of the chamber  50 . 
     As shown in  FIG.  6 B , the discharge opening  58  including the first discharge opening  58   a  and the second discharge opening  58   b  is formed in the side wall  53 . The discharge opening  58  is an opening through which a gas is discharged from the inner space S of the chamber  50 . The first discharge opening  58   a  and the second discharge opening  58   b  (the discharge opening  58 ) are formed in the central portion of the side wall  53  in the left-right direction. In the left-right direction, the lengths of the first discharge opening  58   a  and the second discharge opening  58   b  are smaller than the length of the carry-in/out opening  57 . The first discharge opening  58   a  and the second discharge opening  58   b  are arranged in the vertical direction, and the second discharge opening  58   b  is located above the first discharge opening  58   a . The carry-in/out opening  57  and the discharge opening  58  (the first discharge opening  58   a  and the second discharge opening  58   b ) are arranged with the heating unit  42  interposed therebetween in the front-back direction. 
     &lt;Partition Unit Flow Path Control Unit&gt; 
     As shown in  FIG.  3   , the inner space S of the chamber  50  is partitioned into the processing space S 1  and the retreat space S 2  by the partition unit  60 . The processing space S 1  is a space where the workpiece W supported by the heating unit  42  is exposed, and the retreat space S 2  is a space located above the processing space S 1 . The partition unit  60  is formed into, for example, a plate shape, and may cover the entire area of the heating unit  42  and a part of the bottom wall  56 . A heater may be provided in the partition unit  60 . As the partition unit  60  is heated by the heater, the temperatures of the partition unit  60  and a member connected to partition unit  60  increase, which suppresses adhesion of sublimates to these members.  FIG.  7    is a cross-sectional view taken along a line A-A of  FIG.  3   , and the line A-A passes through the processing space S 1 . 
     The processing space S 1  is partitioned by the side wall  53 , the side wall  54 , the side wall  55 , the bottom wall  56 , the heating unit  42 , the shutter unit  70  and a lower surface of the partition unit  60 . The first discharge opening  58   a  is formed in a portion of the side wall  53  that partitions the processing space S 1 . When viewed from the top (when the heating unit  42  is viewed from the top), a direction connecting the center of the heating unit  42  and the center of the first discharge opening  58   a  corresponds to the front-back direction. When viewed from the top, a direction orthogonal to the direction connecting the center of the heating unit  42  (the center of the hot plate  43 ) and the center of the first discharge opening  58   a  corresponds to the left-right direction (width direction). The first discharge opening  58   a  is an opening through which a gas is discharged from the processing space S 1 . The first discharge opening  58   a  is opened to the processing space S 1 . When a gas is discharged from the processing space S 1 , the gas flows toward the first discharge opening  58   a  in the processing space S 1 . In the left-right direction, the first discharge opening  58   a  has a smaller length than the heating unit  42 . 
     The heating treatment unit  40  may be provided with a flow path control unit  62 . The flow path control unit  62  forms a flow path for a gas that flows toward the first discharge opening  58   a  between the heating unit  42  and the side wall  53 . Since the flow path control unit  62  is provided, it becomes easy for a gas in the processing space S 1  to flow toward the first discharge opening  58   a . The flow path control unit  62  is provided between the heating unit  42  and the side wall  53  when viewed from the top. The flow path control unit  62  has, for example, an inner wall  63  and an inner wall  64 . 
     The inner wall  63  is provided around the heating unit  42  in the processing space S 1 . The inner wall  63  is provided to partition the processing space S 1  into an accommodation space S 11  including the heating unit  42  and a control space S 12  including the first discharge opening  58   a . The inner wall  63  extends between the bottom wall  56  and the partition unit  60  in the vertical direction as shown in  FIG.  8   . An upper end of the inner wall  63  is connected to the lower surface of the partition unit  60 , and a lower end of the inner wall  63  is connected to an upper surface of the bottom wall  56 . One end of the inner wall  63  in the left-right direction is connected to the side wall  54 , and the other end of the inner wall  63  in the left-right direction is connected to the side wall  55 . When viewed from the top, the inner wall  63  may have a circular arc shape that extends along the circumferential direction around the center of the heating unit  42 . In the left-right direction, the length of the inner wall  63  may be greater than the length of the workpiece W on the heating unit  42 . 
     The inner wall  63  includes a plurality of discharge holes  63   a  arranged in an extension direction of the inner wall  63 . Each of the plurality of discharge holes  63   a  is an opening that connects the accommodation space S 11  and the control space S 12 . A gas in the accommodation space S 11  is introduced into the control space S 12  through the plurality of discharge holes  63   a . Each of the plurality of discharge holes  63   a  penetrates through the inner wall  63  along the front-back direction. This means that an inner wall forming the penetrating holes (openings) penetrates through the inner wall  63  so as to extend along the front-back direction. 
     The plurality of discharge holes  63   a  formed in the inner wall  63  is scattered in the left-right direction. In the left-right direction, the distance between end portions of a region where the plurality of discharge holes  63   a  is formed in the inner wall  63  may be greater than 90% of the diameter of the workpiece W or may be greater than the diameter of the workpiece W. The distance between the end portions of the region where the discharge holes  63  are formed is defined as the shortest distance between a right end portion of the discharge hole  63   a  at the rightmost end and a left end portion of the discharge hole  63   a  at the leftmost end in the left-right direction. 
     The inner wall  64  (second inner wall) is located between the inner wall  63  and the side wall  53 . The inner wall  64  is provided to partition the control space S 12  into a buffer space including the inner wall  63  and a discharge space including the first discharge opening  58   a . The inner wall  64  extends between the bottom wall  56  and the partition unit  60  in the vertical direction as shown in  FIG.  8   . An upper end of the inner wall  64  is connected to the lower surface of the partition unit  60 , and a lower end of the inner wall  64  is connected to the upper surface of the bottom wall  56 . One end of the inner wall  64  in the left-right direction is connected to the side wall  54 , and the other end of the inner wall  64  in the left-right direction is connected to the side wall  55 . The inner wall  64  may have a circular arc shape that extends along the circumferential direction around the center of the heating unit  42  (the hot plate  43 ). In the left-right direction, the length of the inner wall  64  may be approximately identical to the length of the inner wall  63 . 
     The inner wall  64  includes a plurality of discharge holes  64   a  (a plurality of second discharge holes) arranged in an extension direction of the inner wall  64 . Each of the plurality of discharge holes  64   a  is an opening that connects the buffer space and the discharge space. A gas in the accommodation space S 11  is introduced into the buffer space through the plurality of discharge holes  63   a  formed in the inner wall  63  and then introduced into the discharge space through the plurality of discharge holes  64   a  formed in the inner wall  64 . Each of the plurality of discharge holes  64   a  penetrates through the inner wall  64  along the front-back direction. 
     The plurality of discharge holes  64   a  formed in the inner wall  64  is scattered in the left-right direction. The plurality of discharge holes  64   a  is formed to disperse a flow rate of a gas flowing through the plurality of discharge holes  63   a  formed in the inner wall  63  (to reduce deviation in the left-right direction) by exhaust through the first discharge opening  58   a . The first discharge opening  58   a  is located at a central portion in the left-right direction of the processing space S 1 . Therefore, assuming that the plurality of discharge holes  63   a  is formed at an approximately equal distance from each other in the inner wall  63  without the inner wall  64  (the plurality of discharge holes  64   a ), a gas flow rate becomes higher in some discharge holes  63   a  located at the central portion in the left-right direction than in the other discharge holes  63   a . In this case, the flow of gas becomes stronger above a central portion in the left-right direction of the workpiece W on the heating unit  42  than in the other portion. 
     The arrangement of the plurality of discharge holes  63   a  in the inner wall  63  is different from the arrangement of the plurality of discharge holes  64   a  in the inner wall  64 . For example, the number of the plurality of discharge holes  63   a  is different from the number of the plurality of discharge holes  64   a , and the distance between adjacent discharge holes is changed in different ways from each other. At least some of the plurality of discharge holes  64   a  do not overlap the plurality of discharge holes  63   a  when viewed from the front-back direction. 
       FIG.  9    is a cross-sectional view taken along a line B-B of  FIG.  3   , and the line B-B passes through the retreat space S 2 . The partition unit  60  is fixed at the side wall  54 , the side wall  55  and the side wall  53 . The partition unit  60  may be integrally formed with the chamber  50 . The retreat space S 2  is partitioned by an upper surface of the partition unit  60 , the side wall  52 , the side wall  53 , the side wall  54 , the side wall  55  and a lower surface of the top plate  51 . 
     The second discharge opening  58   b  is formed in a portion of the side wall  53  that partitions the retreat space S 2 . When viewed from the top, the center of the second discharge opening  58   b  (central portion in the left-right direction) may be approximately matched with the center of the first discharge opening  58   a  (central portion in the left-right direction). The second discharge opening  58   b  is an opening through which a gas is discharged from the retreat space S 2 . The second discharge opening  58   b  is opened to the retreat space S 2 . When a gas is discharged from the retreat space S 2 , the gas flows toward the second discharge opening  58   b  in the retreat space S 2 . In the left-right direction, the second discharge opening  58   b  has a smaller length than the heating unit  42 . 
     The retreat space S 2  and the processing space S 1  are connected to each other via a connection port  69 . The connection port  69  is formed between the partition unit  60  and the side wall  52 . The connection port  69  is located between the side wall  52  and the heating unit  42  (the workpiece W on the heating unit  42 ) in the front-back direction. The connection port  69  is opened extending along the side wall  52 . The length of the connection port  69  in the left-right direction may be greater than the diameter of the workpiece W on the heating unit  42 . In the left-right direction, the connection port  69  has a greater length than the second discharge opening  58   b . The retreat space S 2  may include a flow path S 21  (first flow path) including the connection port  69  and a flow path S 22  (second flow path) having a smaller width in the left-right direction than the flow path S 21 . 
     The heating treatment unit  40  may include a flow path forming member  66  and a flow path forming member  67 . The flow path forming member  66  and the flow path forming member  67  are configured to partition the retreat space S 2  into a region where a gas flows toward the second discharge opening  58   b  and a region where the gas does not flow. When viewed from the top, the flow path forming member  66  and the flow path forming member  67  are axisymmetric with respect to a virtual line passing through a central portion of the chamber  50  in the left-right direction and extending in the front-back direction. The flow path forming member  66  and the flow path forming member  67  are inner walls extending between the upper surface of the partition unit  60  and the lower surface of the top plate  51 . An upper end of the flow path forming member  66  and an upper end of the flow path forming member  67  are connected to the lower surface of the top plate  51 , and a lower end of the flow path forming member  66  and a lower end of the flow path forming member  67  are connected to the upper surface of the partition unit  60 . The flow path forming member  66  includes an inner wall  66   a  and an inner wall  66   b , and the flow path forming member  67  includes an inner wall  67   a  and an inner wall  67   b.    
     One end of the inner wall  66   a  is connected to a portion of the side wall  54  close to the connection port  69 , and the inner wall  66   a  extends with inclination to both the left-right direction and the front-back direction. The position of the other end of the inner wall  66   a  in the left-right direction is approximately matched with the position of an end portion of the second discharge opening  58   b  close to the side wall  54 . The other end of the inner wall  66   a  is connected to one end of the inner wall  66   b . The inner wall  66   b  extends to the side wall  53  along the front-back direction. 
     One end of the inner wall  67   a  is connected to a portion of the side wall  55  close to the connection port  69 , and the inner wall  67   a  extends with inclination to both the left-right direction and the front-back direction. The position of the other end of the inner wall  67   a  in the left-right direction is approximately matched with the position of an end portion of the second discharge opening  58   b  close to the side wall  55 . The other end of the inner wall  67   a  is connected to one end of the inner wall  67   b . The inner wall  67   b  extends to the side wall  53  along the front-back direction. 
     The distance between the inner wall  66   a  and the inner wall  67   a  in the left-right direction decreases as they become closer to the second discharge opening  58   b . The distance between the inner wall  66   b  and the inner wall  67   b  in the left-right direction remains approximately unchanged even if the positions thereof in the front-back direction are changed. With the above-described configuration, the flow path S 21 , the flow path S 22  and two regions where a gas does not flow are formed in the retreat space S 2 . In the retreat space S 2 , the flow path S 21  is a region between the side wall  52  and a virtual plane connecting a connection portion of the inner wall  66   a  with respect to the inner wall  66   b  and a connection portion of the inner wall  67   a  with respect to the inner wall  67   b . In the retreat space S 2 , the flow path S 22  is a region between the virtual plane and the second discharge opening  58   b . The two regions where a gas does not flow refer to regions other than the flow path S 21  and the flow path S 22  in the retreat space S 2 . 
     When viewed from the top, at least a part of the flow path S 22  is provided overlapping the heating unit  42 . When viewed from the top, the boundary between the flow path S 21  and the flow path S 22  overlaps the heating unit  42 . In the processing space S 1 , the flow path is narrowed at a region near the first discharge opening  58   a  and around the heating unit  42 , whereas in the retreat space S 2 , the flow path is narrowed at a position overlapping the heating unit  42 . In the regions where a gas does not flow in the retreat space S 2 , wiring, sensors and the like may be provided. 
     &lt;Shutter Unit&gt; 
       FIG.  10 A  and  FIG.  10 B  illustrate an example operation of the shutter unit  70 . The shutter unit  70  is located to cover the side of the carry-in/out opening  57  formed in the side wall  52 . The shutter unit  70  may be provided in the base  24 . The shutter unit  70  includes, for example, a shutter member  72  and a driver  74 . 
     The shutter member  72  is configured to cover the side of the carry-in/out opening  57 . The shutter member  72  is formed into a plate shape and extends along a plane (Y-Z plane in the drawings) intersecting the front-back direction. When viewed from the front-back direction, the shutter member  72  has a greater size than the carry-in/out opening  57 . The driver  74  includes a driving source such as an electric motor or a cylinder, and moves the shutter member  72  in the vertical direction. When the shutter member  72  is driven by the driver  74 , a closed state where the carry-in/out opening  57  is covered from the side and an open state where the carry-in/out opening  57  is opened are switched. 
     When the shutter member  72  is located at a position closest to the base  24  by the driver  74 , the shutter member  72  covers the entire area of the carry-in/out opening  57  and the carry-in/out opening  57  is put in the closed state when viewed from the side. In this case, the inner space S is formed by an inner wall of the shutter member  72  and the chamber  50  in the chamber  50 . When the shutter member  72  is located at a position farthest from the base  24  by the driver  74 , the shutter member  72  does not overlap the carry-in/out opening  57  and the carry-in/out opening  57  is put in the open state when viewed from the side. As described above, the shutter member  72  switches between the closed state where the carry-in/out opening  57  is covered from the side and the open state where the carry-in/out opening  57  is opened. 
       FIG.  11    is a schematic side view illustrating the shutter member  72  and a part of the chamber  50 . The shutter member  72  may be provided in the base  24  except a connection portion with respect to the driver  74  so as not to be in contact with the other members. The shutter member  72  is provided at a gap g 1  with the side wall  52  of the chamber  50 . There is a gap between the shutter member  72  and the bottom wall  56 . In either of the closed state and the open state, the shutter member  72  is not in contact with the chamber  50 . 
     The shutter member  72  in the closed state (closest to the base  24 ) is provided at a gap g 2  with the base  24 . The gap g 2  is formed under the shutter member  72 . The gap g 1  may be greater than the gap g 2 . For example, the gap g 1  (the size of the gap g 1 ) is from about 0.8 mm to about 1.6 mm, and the gap g 2  (the size of the gap g 2 ) is from about 0.2 mm to about 0.7 mm. Also, the base  24  may be equipped with a support that supports a part of a lower surface of the shutter member  72 . In this case, the gap g 2  corresponds to a space except the support between the lower surface of the shutter member  72  and the base  24 . 
     &lt;Exhaust Unit&gt; 
       FIG.  12    is a schematic diagram illustrating an example of the inside of the exhaust unit  80  and an example of the switching unit  90 . The exhaust unit  80  is configured to discharge a gas from each of the processing space S 1  and the retreat space S 2 . The exhaust unit  80  includes a pipe  82  and a pipe  84 . The pipe  82  is a member that forms a channel C 1  and a channel C 2 . The channel C 1  (first channel) is connected to the first discharge opening  58   a  opened to the processing space S 1 , and an exhaust gas discharged from the processing space S 1  flows through the channel C 1 . The channel C 2  (second channel) is connected to the second discharge opening  58   b  opened to the retreat space S 2 , and an exhaust gas discharged from the retreat space S 2  flows through the channel C 2 . 
     The pipe  82  extends, for example, in the front-back direction. The channel C 1  and the channel C 2  are arranged in the vertical direction. A connection port  81   a  connected to the first discharge opening  58   a  is provided at an upstream end of the channel C 1 , and a connection port  81   b  connected to the second discharge opening  58   b  is provided at an upstream end of the channel C 2 . In the present disclosure, the terms “upstream” and “downstream” are used based on the flowing direction of a gas. As the gas is exhausted by the exhaust unit  80 , the gas flows from the upstream side toward the downstream side in the chamber  50  and in the exhaust unit  80 . 
     The pipe  84  is a member that forms a common channel C 3  connected to each of the channel C 1  and the channel C 2 . The common channel C 3  is connected to the channel C 1  via a connection port  87   a  provided at a downstream end of the channel C 1  and connected to the channel C 2  via a connection port  87   b  provided at a downstream end of the channel C 2 . The connection port  87   a  may be an opening penetrating through the inner wall in the front-back direction, and the connection port  87   b  may be an opening penetrating through the inner wall in the vertical direction. The connection port  87   b  is located at a downstream side relative to the connection port  87   a  in the front-back direction and located higher than the connection port  87   a.    
     In the common channel C 3 , the exhaust gas introduced from the channel C 1  or the channel C 2  may flow downwards. A downstream end of the common channel C 3  (a discharge port  81   c  formed at a lower end portion of the pipe  84 ) is connected to another exhaust pipe. The other exhaust pipe may be connected to pipes of the exhaust units in the plurality of heat treatment units U 2 . During the operation of the coating and developing apparatus  2 , the gas is continuously exhausted from the other exhaust pipe through the discharge port  81   c  and the common channel C 3 . 
     The exhaust unit  80  (the pipe  82 ) is mounted to the side wall  53  of the chamber  50  via a fixing member. The exhaust unit  80  can be detachably attached to the chamber  50 . In other words, the exhaust unit  80  is separably mounted to the chamber  50 . As shown in  FIG.  4    or  FIG.  5   , the exhaust unit  80  includes a flange  83  and a pair of mounting members  88 . The flange  83  is formed at an upstream end of the pipe  82  and extends outwards from an outer wall of the pipe  82 . When viewed from the front-back direction, an outer periphery of the flange  83  may have a rectangular shape (see  FIG.  12   ). 
     The pair of mounting members  88  extend from left and right end portions of the flange  83  toward a downstream side. Each of the pair of mounting members  88  is provided away from the pipe  82 . Each of the mounting members  88  has a gap with the pipe  82  in the left-right direction. A fixing member  89  that fixes the chamber  50  and the exhaust unit  80  is mounted to each of the pair of mounting members  88 . The fixing member  89  may be any member as long as it can fix the chamber  50  and the exhaust unit  80 . 
     The fixing member  89  includes, for example, a hook portion. When the hook portion is insertion-fitted to a receiving portion formed at the side of the protrusion of the side wall  53  of the chamber  50 , the fixing member  89  fixes the chamber  50  and the exhaust unit  80  to each other. When the fixing member  89  fixes the chamber  50  and the exhaust unit  80 , the fixing member  89  may be switched to a fixed state by manipulation of an operator. When the fixing between the chamber  50  and the exhaust unit  80  is released, the fixing member  89  may be switched to a released state by manipulation of the operator. Unlike the above-described example, the exhaust unit  80  may be integrally formed with the chamber  50 . 
     &lt;Switching Unit&gt; 
     Referring back to  FIG.  12   , the switching unit  90  is provided within the exhaust unit  80 . The switching unit  90  connects the channel C 1  and the common channel C 3  in the first exhaust state where a gas is not discharged from the retreat space S 2  but discharged through the processing space S 1 . When the gas is continuously exhausted from the common channel C 3  and the switching unit  90  opens the channel C 1  and closes the channel C 2 , the gas is not discharged from the retreat space S 2  but discharged from the processing space S 1 . The switching unit  90  connects the channel C 2  and the common channel C 3  in the second exhaust state where the gas is not discharged from the processing space S 1  but discharged through the retreat space S 2 . When the gas is continuously exhausted from the common channel C 3  and the switching unit  90  opens the channel C 2  and closes the channel C 1 , the gas is not discharged from the processing space S 1  but discharged from the retreat space S 2 . 
     The switching unit  90  includes, for example, a closing member  92 , a shaft member  94  and a driver  96 . The closing member  92  is configured to close each of (either of) the connection port  87   a  between the channel C 1  and the common channel C 3  and the connection port  87   b  between the channel C 2  and the common channel C 3 . The closing member  92  is connected to the shaft member  94 . The shaft member  94  extends in the left-right direction and is rotatable around its central axis line. 
     The driver  96  includes a driving source such as an electric motor, and rotates the shaft member  94  around the axis line. When the shaft member  94  rotates, the closing member  92  rotates around the central axis line. The closing member  92  rotates around the central axis line between a first position where the closing member  92  closes the connection port  87   b  and a second position where the closing member  92  closes the connection port  87   a.    
     When the closing member  92  is located at the first position where the closing member  92  closes the connection port  87   b , the channel C 1  is opened to (connected to) the common channel C 3  and the channel C 2  is closed. Thus, it becomes the first exhaust state where the gas is not discharged from the retreat space S 2  through the second discharge opening  58   b  and the channel C 2  but discharged from the processing space S 1  through the first discharge opening  58   a  and the channel C 1 . 
     When the closing member  92  is located at the second position where the closing member  92  closes the connection port  87   a , the channel C 2  is opened to (connected to) the common channel C 3  and the channel C 1  is closed. Thus, it becomes the second exhaust state where the gas is not discharged from the processing space S 1  through the first discharge opening  58   a  and the channel C 1  but discharged from the retreat space S 2  through the second discharge opening  58   b  and the channel C 2 . As described above, when the closing member  92  of the switching unit  90  is switched in position, the first exhaust state and the second exhaust state are switched. The closing member  92  is configured to open the channel C 1  and close the channel C 2  in the first exhaust state, and configured to close the channel C 1  and open the channel C 2  in the second exhaust state. 
     (Attachment and Detachment of Chamber) 
       FIG.  13   ,  FIG.  14   ,  FIG.  15 A  and  FIG.  15 B  illustrate examples of attachment and detachment of the chamber  50 . The chamber  50  is configured to be detachably attached to a base member of the heat treatment unit U 2 . The base member of the heat treatment unit U 2  is a member that fixes or supports various members at respective predetermined positions in the heat treatment unit U 2 . In the heat treatment unit U 2 , the heating unit  42  is provided in the base member and the shutter unit  70  (the shutter member  72 ) is provided in the base member. The base member of the heat treatment unit U 2  includes, for example, the housing  20 , the base  24  and the base  25 . The chamber  50  is separably mounted to the base member of the heat treatment unit U 2 . When the chamber  50  is separated, the heating unit  42  and the shutter unit  70  remains on the base member. 
     The top plate  51  and the side walls  52 ,  53 ,  54  and  55  of the chamber  50  are integrally formed (as one body) and thus can be separated from the base member and can be mounted to the base member. That is, in a state where the top plate  51  and the side walls  52  to  55  are connected to each other, the entire chamber  50  can be separated from the base member and can be mounted to the base member. In a state where the bottom wall  56  is fixed to the chamber  50 , the chamber  50  and the bottom wall  56  are integrally formed (as one body) and thus can be separated from the base member and can be mounted to the base member. In a state where the partition unit  60  is fixed to the chamber  50 , the partition unit  60  is movable together with the chamber  50  with respect to the base member. That is, when the chamber  50  is separated, the partition unit  60  is also separated, and when the chamber  50  is mounted, the partition unit  60  is also mounted. 
     When the chamber  50  is located at an installation position in the heat treatment unit U 2  and fixed to the base member by a fixing member such as a bolt or the like, the chamber  50  may be mounted to the base member. When the chamber  50  is located at the installation position, an inner space of the chamber  50  surrounds the heating unit  42  (the workpiece W on the heating unit  42 ), and, thus, the above-described inner space S may be formed. When the fixing by the fixing member is released and the chamber  50  is moved from the installation position (for example, moved to the outside of the housing  20 ), the chamber  50  may be separated from the base member. The chamber  50  may be mounted and separated by the operator using a jig. 
     The heat treatment unit U 2  includes a guide unit  210 . The guide unit  210  is a member that guides the movement of the chamber  50  in a predetermined direction along an upper surface of the heating unit  42  (or the upper surface of the hot plate  43 ). The direction in which the chamber  50  is guided by the guide unit  210  (hereinafter, referred to as “driving direction”) may be the front-back direction. In this case, when the chamber  50  is separated, it may be separated from the base member while sliding in the front-back direction, and when the chamber  50  is mounted, it may be mounted to the base member while sliding in the front-back direction. If the driving direction is the front-back direction, the exhaust unit  80  discharges a gas from the inner space S of the chamber  50  so that the gas can flow toward one side along the driving direction. 
     When the chamber  50  is mounted, the guide unit  210  guides the chamber  50  moving toward the installation position. When the chamber  50  is mounted, the chamber  50  slides in a direction from the heating unit  42  toward the shutter unit  70  so as to be mounted to the installation position. When the chamber  50  is separated, the guide unit  210  guides the chamber  50  moving from the installation position. When the chamber  50  is separated, the chamber  50  slides in a direction from the shutter unit  70  toward the heating unit  42  so as to be taken out of the housing  20 . 
     The guide unit  210  includes a rail member  212  and fixing members  214  and  214 . The rail member  212  extends along the driving direction. The rail member  212  may extend along the front-back direction. The rail member  212  is located at an outer side than the chamber  50  in the left-right direction. As shown in  FIG.  13   , when the chamber  50  is located at the installation position, the rail member  212  is provided to face a side wall (for example, the side wall  55 ) on one side of the chamber  50  in the left-right direction. The length of the rail member  212  in the front-back direction may be equal to the length of the side wall  55  of the chamber  50 . 
     The fixing members  214  and  214  are configured to fix the rail member  212  to the base member. The rail member  212  is supported by the fixing members  214  and  214  and thus is fixed at a predetermined position in the housing  20 . The heat treatment unit U 2  may include another guide unit  210 , or a pair of guide units  210  may be provided with the heating unit  42  and the chamber  50  interposed therebetween in the left-right direction. 
     A protrusion  242  and a roller  244  are provided on an outer wall of the chamber  50  (for example, an outer surface of the side wall  55 ) in the left-right direction. The protrusion  242  protrudes outwards from the side wall of the chamber  50  and extends along the driving direction. The roller  244  is a member that is rotatable with respect to the chamber  50 . The roller  244  is provided to be arranged with the protrusion  242  in the driving direction, and is located closer to the shutter unit  70  (the side wall  52  where the carry-in/out opening  57  is formed) than the protrusion  242 . That is, in a state where the chamber  50  is located at the installation position, the shutter unit  70  (or the side wall  52 ), the roller  244  and the protrusion  242  are arranged in this order in the front-back direction. 
     The rail member  212  includes a rail main body  212   a  and a recess  212   b  that is recessed downwards from an upper surface of the rail main body  212   a . The recess  212   b  is formed at an end portion of the rail member  212  (the rail main body  212   a ) close to the shutter unit  70 .  FIG.  13    or  FIG.  15 A  illustrates an example of a state where the chamber  50  is located at the installation position. When the chamber  50  is located at the installation position, a lower surface of the protrusion  242  is supported by the rail main body  212   a , and the roller  244  provided in the chamber  50  is accommodated in the recess  212   b.    
     The guide unit  210  may be equipped with a roller  218 . The roller  218  is provided on an inner surface of the rail main body  212   a  (a surface facing the side wall of the chamber  50 ). The roller  218  is rotatable with respect to the rail member  212 . The roller  218  is located at a different position from the recess  212   b  in the driving direction. The protrusion  242  provided in the chamber  50  includes an accommodation portion  242   a  where the roller  218  is accommodated when the chamber  50  is located at the installation position. With the above-described configuration, when the chamber  50  is located at the installation position, the roller  244  provided in the chamber  50  is accommodated in the recess  212   b  of the rail member  212 . Also, the roller  218  provided in the rail member  212  is accommodated in the accommodation portion  242   a  of the protrusion  242  provided in the chamber  50 . 
       FIG.  14    or  FIG.  15 B  illustrates an example of a state where the chamber  50  (the chamber  50 , the bottom wall  56  and the partition unit  60 ) is separated from the installation position or where the chamber  50  (the chamber  50 , the bottom wall  56  and the partition unit  60 ) is mounted to the installation position. When the chamber  50  moves along the driving direction, the roller  244  provided in the chamber  50  drives (moves with rotation) on the rail main body  212   a . A protrusion  243  is provided under the protrusion  242  on a side surface of the chamber  50 . The protrusion  243  less protrudes from the side surface of the chamber  50  than the protrusion  242 . 
     When the chamber  50  moves, it is guided along the driving direction while the protrusion  243  is supported by the roller  218  of the guide unit  210 . When the operator applies force in the driving direction while holdings one end of the chamber  50 , the chamber  50  may also move along the driving direction. When the chamber  50  is attached and detached (mounted and separated), a side wall of the housing  20  where the exhaust unit  80  is located may be opened. 
     (Control Device) 
     The control device  100  is composed of one or more control computers. The control device  100  controls the switching unit  90  to switch from the second exhaust state (exhaust through the retreat space S 2 ) to the first exhaust state (exhaust through the processing space S 1 ) at least during heating of the workpiece W by the heating unit  42 . 
     The control device  100  includes, for example, a circuit  120  show in  FIG.  16   . The circuit  120  is composed of one or more processors  122 , a memory  124 , a storage  126 , an input/output port  128  and a timer  132 . The storage  126  has a computer-readable recording medium such as a hard disk or the like. The recording medium stores programs for executing a substrate processing method to be described later by the control device  100 . The recording medium may be implemented by a portable medium such as a non-volatile semiconductor memory, a magnetic disk or an optical disk. 
     The memory  124  temporarily stores thereon the programs loaded from the recording medium of the storage  126  and an operation result by the processor  122 . The processor  122  executes the programs in cooperation with the memory  124 . The input/output port  128  is configured to perform an input and an output of electric signals with respect to the liquid treatment unit U 1  and the heat treatment unit U 2  in response to instructions from the processor  122 . The timer  132  measures an elapsed time by, for example, counting a reference pulse of a predetermined cycle. 
     [Substrate Processing Method] 
     Hereinafter, a series of processings performed by the control device  100  in a heat treatment for the workpiece W will be described as an example of a substrate processing method (heat treatment method). The series of processings are performed in a state where a gas is continuously exhausted by the exhaust unit  80  and the hot plate  43  is continuously heated by the heater in the heating unit  42 .  FIG.  17    is a flowchart showing a series of processings performed by the control device  100  in a heat treatment for one workpiece W. 
     The control device  100  performs a process S 91  first in a state where the exhaust unit  80  can exhaust a gas in the first exhaust state and the workpiece W on which a film of a processing liquid has been formed is supported on the cooling plate  31  of the transfer unit  30 . In the process S 91 , for example, the control device  100  controls the driver  74  to raise the shutter member  72  and switches from the closed state where the carry-in/out opening  57  for the workpiece W in the chamber  50  is closed to the open state where the carry-in/out opening  57  is opened. 
     Then, the control device  100  performs a process S 92 . In the process S 92 , for example, the control device  100  controls the transfer unit  30  and the elevating unit  44  to carry the workpiece W into the chamber  50  from the cooling plate  31  and deliver the workpiece W from the cooling plate  31  to the heating unit  42 .  FIG.  18 A  illustrates an example of a state where the workpiece W is carried into the chamber  50 . 
     Thereafter, the control device  100  performs a process S 93 . In the process S 93 , for example, the control device  100  controls the switching unit  90  in order for the exhaust unit  80  to exhaust a gas in the second exhaust state. For example, the control device  100  drives the closing member  92  by the driver  96  to close the channel C 1  connected to the processing space S 1  and the first discharge opening  58   a  and allow the channel C 2  connected to the retreat space S 2  and the second discharge opening  58   b  to be opened to the common channel C 3 . Thus, the exhaust unit  80  is put in a state where a gas can be exhausted from the retreat space S 2 . 
     Subsequently, the control device  100  performs a process S 94 . In the process S 94 , for example, the control device  100  controls the shutter unit  70  to switch to the closed state where the carry-in/out opening  57  is covered from the side. The control device  100  may control the driver  74  to move the shutter member  72  downwards. When the shutter member  72  covers the carry-in/out opening  57 , the inner space S in which the workpiece W is heated is formed by the shutter member  72 , the heating unit  42  and the chamber  50  and heating of the workpiece W is started. 
     The exhaust unit  80  is put in a state where a gas can be exhausted in the second exhaust state before the shutter member  72  is closed. Therefore, when the inner space S is formed, the exhaust unit  80  discharges the gas from the retreat space S 2  as shown in  FIG.  18 B . The gap g 1  is formed between the shutter member  72  and the side wall  52 , and the gas is introduced into the inner space S through the gap g 1 . The gas introduced into the inner space S through the gap g 1  flows through the connection port  69 , the retreat space S 2  (the flow paths S 21  and S 22 ), the channel C 2  and the common channel C 3  of the exhaust unit  80 . Thus, in the initial stage of the heat treatment for the workpiece W, it is possible to suppress the generation of an air flow in the processing space S 1 . 
     Then, the control device  100  performs a process S 95 . In the process S 95 , for example, the control device  100  stands by until a predetermined switching time elapses from the end time of the process S 94  (heating start timing). The switching time is previously set, and may be set such that, for example, the film of the processing liquid on the workpiece W to be processed can be solidified to a certain extent. The switching time may be set to about several tens of seconds. 
     Thereafter, the control device  100  performs a process S 96 . In the process S 96 , for example, the control device  100  controls the switching unit  90  to switch from the second exhaust state to the first exhaust state. For example, the control device  100  drives the closing member  92  by the driver  96  to allow the channel C 1  connected to the processing space S 1  and the first discharge opening  58   a  to be opened to the common channel C 3  and close the channel C 2  connected to the retreat space S 2  and the second discharge opening  58   b . Thus, during heating of the workpiece W, exhaust by the exhaust unit  80  is performed in the first exhaust state switched from the second exhaust state. In the first exhaust state, the gas in the processing space S 1  is discharged through the first discharge opening  58   a  and the channel C 1  as shown in  FIG.  19   . Thus, sublimates generated in the processing space S 1  during heating of the workpiece W can be discharged to the outside of the chamber  50 . 
     Subsequently, the control device  100  performs a process S 97 . In the process S 97 , for example, the control device  100  stands by until a predetermined heating time elapses from the end time of the process S 94  (heating start timing). The heating time is previously set and may be about 1.5 to 5.0 times longer than the switching time. 
     Then, the control device  100  performs processes S 98  and S 99 . In the process S 98 , for example, the control device  100  controls the shutter unit  70  to open the carry-in/out opening  57  for the workpiece W and allow the inner space of the chamber  50  to be opened (raises the shutter member  72  by the driver  74 ). In the process S 99 , for example, the control device  100  controls the transfer unit  30  and the elevating unit  44  to deliver the workpiece W from the heating treatment unit  40  to the cooling plate  31  of the transfer unit  30  and carry the workpiece W out of the chamber  50 . 
     In this way, the series of processings performed by the control device  100  in the heat treatment for the workpiece W are ended. The control device  100  may repeatedly perform the series of processings in the processes S 91  to S 99  for each of a subsequent plurality of workpieces W. The above-described series of processings are just an example and can be modified appropriately. In the above-described series of processings, the control device  100  may perform the processes in parallel, or may change the order of processes. The control device  100  may perform processings different from those described above in the respective processes. 
     [Maintenance Method] 
     When a heat treatment in the heat treatment unit U 2  is repeated, sublimates adhere to a portion of the chamber  50  and the partition unit  60  that partitions the processing space S 1 . For this reason, the maintenance including cleaning of the chamber  50  and the partition unit  60  needs to be performed regularly. A maintenance method to be described below is performed by the operator while the coating and developing apparatus  2  (the substrate processing system  1 ) is not operated. 
     First, the operator performs a process of separating the exhaust unit  80  from the chamber  50 . For example, the operator releases a locked state of the fixing member  89  mounted to the mounting members  88  of the exhaust unit  80  and then separates the exhaust unit  80  from the chamber  50 . The operator may also separate the exhaust unit  80  from another pipe (for example, a pipe where exhaust gases from a plurality of heat treatment units U 2  join) connected to the common channel C 3  of the exhaust unit  80 .  FIG.  20 A  illustrates an example of a state where the exhaust unit  80  is being separated from the chamber  50 . 
     Then, the operator performs a process of separating the chamber  50  from the base member of the heat treatment unit U 2 . When the chamber  50  is separated, the bottom wall  56 , the partition unit  60 , the flow path control unit  62  and the flow path forming members  66  and  67  are also separated. For example, the operator releases the locked state made by a fixing member, such as a bolt, fixing the chamber  50  and the base member. Thus, the chamber  50  is put in a state where it is movable with respect to the base member. 
     Further, the operator slides the chamber  50  in a direction away from the shutter unit  70  while upwardly raising the chamber  50  at the installation position. The operator raises the chamber  50  so that the roller  244  accommodated in the recess  212   b  of the rail member  212  can be located on the rail main body  212   a  of the rail member  212  and the protrusion  243  can be located on the roller  218 . Thereafter, the operator slides the chamber  50  along the guide unit  210  in the front-back direction to be taken out of the heat treatment unit U 2 .  FIG.  20 B  illustrates an example of a state where the chamber  50  is separated by being raised once and then slid in the front-back direction. 
     Then, the operator performs a process of cleaning the inside of the chamber  50  to remove sublimates adhering to the inside of the chamber  50 . After the cleaning process, the operator performs a process of installing (mounting) the chamber  50  into the heat treatment unit U 2 . The process of mounting the chamber  50  is performed in a reverse order of the process of separating the chamber  50 . The operator slides the chamber  50  along the guide unit  210  toward the shutter unit  70  until the roller  244  is accommodated in the recess  212   b  and the roller  218  is accommodated in the accommodation portion  242   a . Thus, the chamber  50  is located at the installation position. Then, the operator fixes the chamber  50  to the base member of the heat treatment unit U 2  with a fixing member such as a bolt or the like. 
     Subsequently, the operator mounts the exhaust unit  80  to the chamber  50  and also mounts the common channel C 3  of the exhaust unit  80  to another pipe. In this way, the maintenance operation for one heat treatment unit U 2  is ended. 
     Modification Example 1 
     The configuration in which a chamber is attached and detached is not limited to the above-described example. The rail member  212  can be raised or lowered. As shown in  FIG.  21 A , the heating treatment unit  40  may have a guide unit  210 A instead of the guide unit  210 . The guide unit  210 A has the rail members  212 , the fixing members  214  and actuators  219 . In the guide unit  210 A, for example, the actuator  219  including a cylinder or a motor is provided at a lower portion of the fixing member  214  and serves as an elevation mechanism of the rail member  212 , and the fixing member  214  holding the rail member  212  can be raised and lowered with respect to a base member of the base  24 . As shown in  FIG.  21 A  or  FIG.  21 B , a bulging portion  252  may be provided on an outer wall of the chamber  50  (an outer surface of the side wall), and a roller  254  may be provided at a lower portion of the bulging portion  252 . 
       FIG.  22 A  and  FIG.  22 B  illustrate an example of a state where the chamber  50  is being separated from the installation position. When the chamber  50  is slid, the rail member  212  is raised first by the actuator  219 . Since the chamber  50  and the bottom wall  56  are supported by the rail member  212  via the bulging portion  252 , the chamber  50  and the bottom wall  56  are raised when the rail member  212  is raised. Further, when the roller  254  drives on an upper surface of the rail member  212 , the chamber  50  is slid and guided in the horizontal direction. Furthermore, the guide unit  210 A may not have a recess in which the roller  254  is accommodated, and the bulging portion  252  or a lower surface of the bottom wall  56  may be supported by the rail member  212 . In the above-described configuration according to the modification example 1, a moving route of the chamber  50  can be secured to avoid interference with the other members by raising the rail member  212  with the elevation mechanism before the chamber  50  is unloaded and moved, and, thus, the chamber  50  can be unloaded with safety. 
     Modification Example 2 
     A chamber may be separately formed from a bottom wall, and attachment and detachment of the chamber and attachment and detachment of a member forming the bottom wall may be performed at different timings. As shown in  FIG.  23 A  and  FIG.  23 B , the heating treatment unit  40  may have a chamber  50 B and a base member  260  instead of the chamber  50 , the bottom wall  56  and the guide unit  210 . The chamber  50 B is separately formed from the base member  260 . The chamber  50 B can be detachably attached to the base member  260  and thus can be detachably attached to the base member of the base  24 . The base member  260  has the same function as the above-described bottom wall  56  and serves as a guide unit that guides the movement of the chamber  50 B during attachment and detachment of the chamber  50 B. 
       FIG.  24 A  and  FIG.  24 B  illustrate an example of a state where the chamber  50 B is being separated from the base member.  FIG.  24 A  is a schematic cross-sectional view taken along a line C-C of  FIG.  24 B . The roller  254  may be provided under a side wall extending in the front-back direction of the chamber  50 B. When the chamber  50 B is located at the installation position, the roller  254  may be accommodated in a recess formed in the base member  260  or the side wall of the chamber  50 B may be supported by the base member  260 . When the chamber  50 B is separated, the rollers  254  drive on upper surfaces of both end portions of the base member  260  in the left-right direction, respectively, and, thus, the movement of the chamber  50 B is guided. The chamber  50 B is not connected to the bottom wall, and the chamber  50 B may have the top plate  51  and the side walls  52 ,  53 ,  54  and  55 . The side wall  53  of the chamber  50 B may extend in the left-right direction. 
     After the chamber  50 B is separated, the base member  260  remains on the base member of the base  24 . As shown in  FIG.  25 A , the base member  260  includes a bottom wall  261  and rail units  262  and  262 . The bottom wall  261  includes an exposure hole  261   a  through which the hot plate  43  is exposed. The rail units  262  are provided on side surfaces of both ends of the bottom wall  261  in the left-right direction, respectively. The rail units  262  are integrally formed with the bottom wall  261  that is located beside (around) the hot plate  43  when a heat treatment is performed. The rail units  262  extend in the front-back direction and is configured to enable the roller  254  to drive thereon. 
     In the above-described configuration, the bottom wall  261  and the rail units  262  can be physically separated from a top plate and the side walls of the chamber  50 B and can be detachably attached to the base member independently of the chamber  50 B. The chamber  50 B is guided and moved (unloaded) along the rail units  262  via the roller  254 . That is, the top plate and the side walls that do not interfere with a member, such as the hot plate  43 , in the inner space S in an unloading direction of the chamber  50 B can be unloaded without an elevation operation (large elevation operation). After the chamber  50 B is separated, the bottom wall  261  and the rail units  262  remain on the base member of the base  24 . The bottom wall  261  and the rail units  262  may be loaded on the base member of the base  24  by gravity so as to be easily attached and detached. Otherwise, the bottom wall  261  and the rail units  262  being loaded on the based portion of the base  24  may be fixed at a downstream position in the unloading direction that can be seen by the operator, like the above-described fixing member. After the chamber  50 B is separated, the base member  260  including the bottom wall  261  and the rail units  262  is separated from the base member of the base  24  while sliding in the front-back direction as shown in  FIG.  25 B . 
     Effects of Exemplary Embodiments 
     The coating and developing apparatus  2  described above includes the heating unit  42 , the bottom wall  56  or  261 , the chamber  50  or  50 B and the guide unit. The heating unit  42  is configured to support and heat the workpiece W onto which a processing liquid is supplied. The bottom wall  56  or  261  surrounds the workpiece W supported by the heating unit  42 . The chamber  50  or  50 B includes the top plate  51  covering the heating unit  42  and the side walls  52 ,  53 ,  54  and  55  provided between the bottom wall  56  and the top plate  51 , and is configured to be detachably attached to the base member provided with the heating unit  42 . The guide unit guides the movement of the chamber  50  or  50 B from the installation position, where the inner space of the chamber  50  or  50 B surrounds the workpiece W on the heating unit  42 , in a predetermined driving direction along the upper surface of the heating unit  42 . 
     In the coating and developing apparatus  2 , the chamber  50  or  50 B can be separated from the base member by sliding the chamber  50  or  50 B including the side walls and the top plate in the driving direction along the upper surface of the heating unit  42 . For this reason, the chamber  50  or  50 B can be easily separated even if a space where the chamber  50  or  50 B is accommodated has a small length in the vertical direction. Therefore, it is useful in improving the maintainability. 
     The guide unit  210  may include the rail member  212  extending in the driving direction. The rail member  212  may include the rail main body  212   a  on which the roller  244  provided at the chamber  50  drives; and the recess  212   b  where the roller  244  is accommodated when the chamber  50  is located at the installation position. When the chamber  50  is slid from the installation position in the driving direction, the upper surface of the heating unit  42  may be brought into contact with the chamber  50 . In the above-described configuration, when the chamber  50  is separated from the installation position, the roller  244  needs to be taken out first from the recess  212   b . Accordingly, the chamber  50  is raised and then slid in the driving direction and thus can be separated. Therefore, it is possible to reduce the likelihood of contact between the upper surface of the heating unit  42  and the chamber  50  when the chamber  50  is separated. 
     The coating and developing apparatus  2  described above may further include the exhaust unit  80 . The exhaust unit  80  may be configured to discharge a gas from the inner space S of the chamber  50  such that the gas flows toward one side along the driving direction. In this case, a discharge opening through which the gas is discharged from the inner space of the chamber  50  may be formed at the side of the chamber  50 , and the chamber  50  may be configured such that the bottom wall, the side walls and the top plate can be moved as one body. Accordingly, during the maintenance, many of the members included in the chamber  50  can be separated from the base member. Therefore, it is possible to improve the maintainability of the heat treatment apparatus. 
     The coating and developing apparatus  2  described above may further include the partition unit  60  and the switching unit  90 . The partition unit  60  is configured to partition the inner space of the chamber  50  into the processing space S 1  where the workpiece W on the heating unit  42  is exposed and the retreat space S 2  located above the processing space S 1 . The switching unit  90  is configured to switch between the first exhaust state where the gas is discharged through the processing space S 1  and the second exhaust state where the gas is discharged through the retreat space S 2 . The partition unit  60  may be allowed to be moved together with the chamber  50  with respect to the base member. In this case, while the workpiece W to be processed is heated, the gas can be discharged from the retreat space S 2  in a time zone in which an air flow generated when the exhaust unit  80  discharges the gas greatly affects a film thickness distribution and the gas can be discharged from the processing space S 1  in a time zone in which the air flow less affects the film thickness distribution. Also, since the partition unit  60  moves together with the chamber  50 , the maintenance of the partition unit  60  can be easily performed. Therefore, it is possible to collect sublimates efficiently and reduce an effect on the film thickness distribution as well as secure the maintainability. 
     In the coating and developing apparatus  2  described above, the exhaust unit  80  may be detachably attached to the chamber  50 . Since the exhaust unit  80  is separated from the chamber  50 , it is easy to separate the chamber  50  from the base member and mount the chamber  50  to the base member. Also, the maintenance of the exhaust unit  80  itself can be easily performed compared to a case where the exhaust unit  80  is fixed to the chamber  50 . Therefore, it is possible to further improve the maintainability. 
     In the coating and developing apparatus  2  described above, the exhaust unit  80  may include the pipe  82  forming the channels C 1  and C 2  through which an exhaust gas from the inner space S of the chamber  50  flows and extending in the driving direction, and the mounting members  88  provided away from the pipe  82  and equipped with the fixing member  89  configured to fix the chamber  50  and the exhaust unit  80 . Since a gas is discharged from the inner space S while the workpiece W is heated, the temperature of the pipe  82  may increase. Since the mounting members  88  are provided away from the pipe  82 , the increase in temperature of the fixing member  89  can be suppressed. Accordingly, it is easy to release the fixing between the chamber  50  and the exhaust unit  80 . Therefore, it is possible to further improve the maintainability. 
     The coating and developing apparatus  2  described above may further include the shutter member  72 . The shutter member  72  may be disposed with the gap g 1  therebetween with the side wall  52  of the chamber  50  located at the installation position. The shutter member  72  may be configured to switch between the closed state where the carry-in/out opening  57  for the workpiece W provided in the side wall  52  is covered from the side and the open state where the carry-in/out opening  57  is opened. The shutter member  72  may be provided at the base member. The exhaust unit  80  may discharge a gas from the inner space of the chamber  50  through the discharge opening  58  provided near the heating unit  42 . The carry-in/out opening  57  and the discharge opening  58  may be arranged with the heating unit  42  interposed therebetween in the driving direction. In this case, a part of the shutter member  72  forms a space in which the workpiece W is heated. However, an air flow toward the discharge opening  58  from the carry-in/out opening  57  is generated when the gas is discharged, and, thus, it is difficult for sublimates to adhere to the shutter member  72 . For this reason, during the maintenance, there is no need to separate a member that covers the carry-in/out opening for the workpiece W along with the chamber  50 . Therefore, a configuration of a device configured to attach and detach the chamber  50  to and from the base member can be simplified. 
     In the coating and developing apparatus  2  described above, the guide unit may include the rail unit  262  which extends in the driving direction and on which the roller  254  provided at the chamber  50 B drives. The rail unit  262  may be integrally formed with the bottom wall  261 . The rail unit  262  and the bottom wall  261  may be detachably attached to the base member independently of the chamber  50 B. When the bottom wall is moved in the driving direction, it may interfere with the other members such as a heating unit. In the above-described configuration, the chamber can be attached and detached independently of the bottom wall, and, thus, when the chamber is attached and detached, the amount of vertical movement of the chamber can be reduced. Therefore, it is possible to further improve the maintainability. 
     According to the present disclosure, there is provided the heat treatment apparatus useful in improving the maintainability. 
     From the foregoing, it will be appreciated that various exemplary embodiments of the present disclosure have been described herein for purposes of illustration and various changes can be made without departing from the scope and spirit of the present disclosure. Accordingly, various exemplary embodiments described herein are not intended to be limiting, and the true scope and spirit are indicated by the following claims.