JP2002343708A - Substrate processing system and heat treating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing system and a heat treating method in which an article can be subjected to processing with high uniformity by making uniform the surface temperature of the article in a processing chamber. SOLUTION: A baking system 22 comprises main processing chambers 41, 41a and 41b for baking a substrate W, a sub-processing chamber 42 disposed contiguously to the main processing chambers 41, 41a and 41b through an opening/closing door 45, and means 43 for delivering the substrate W between the main processing chambers 41, 41a and 41b and the sub-processing chamber 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a substrate processing apparatus and a heat treatment method for processing semiconductor substrates and the like.

[0002]

2. Description of the Related Art For example, in a manufacturing process of a semiconductor device, there is provided a photolithography process for performing a predetermined process by various substrate processing apparatuses. In this photolithography process, a substrate (hereinafter, referred to as a semiconductor wafer) to be processed is
In this specification, a resist coating process for forming a resist film on the surface of a “wafer” and a developing process for performing an exposure process on a wafer after the resist application and then a developing process on the wafer are performed. Will be

Conventionally, the resist coating process and the developing process have been performed according to a predetermined sequence across an exposure process in a complex processing system in which various corresponding processing units are provided in one system.

In recent years, the demand for miniaturization of a resist pattern formed on the surface of a wafer has been increasing year by year, and strict control of various parameters that affect the line width of the resist pattern, such as the amount of exposure and the development time, is essential. Is coming. In particular, uniformity of wafer temperature during baking processing by a baking processing apparatus after exposure by an exposure apparatus is extremely important. For example, a pattern having a line width of 130 nm may have a variation of about 10 nm to 15 nm. This is because, in a chemically amplified photoresist used for exposure development of a wafer, the heat treatment temperature after exposure greatly affects the progress of the reaction and affects the pattern size. Thus, if the temperature of the heat treatment chamber changes while the substrate processing of a plurality of wafers is in progress, the dimensions of the wafers will be different. Further, if a temperature distribution exists in the heat treatment chamber, a pattern size distribution also occurs in the wafer plane.

FIGS. 9 (a) and 9 (b) are sectional views of a conventional baking apparatus during operation. A temperature control plate 92 is provided inside a processing container 91 forming the baking processing device. Temperature sensors 93a, 93b... 93n are mounted inside the temperature adjusting plate 92. The processing container 91 is provided with a detachable lid 94. The lid 94 is detached from the processing container 91 when a wafer W to be processed is inserted into or removed from the processing container 91, and is removed when the wafer W is stored in the processing container 91 and subjected to baking processing. Close to the processing container 91
Seal the inside. The baking process for the wafer W is performed by temperature sensors 93a, 93b,.
Control is performed using the output value of n.

[0006]

However, in the above-described baking processing apparatus, the lid that is attached to and detached from the processing container is
When the processing container is closed close to the processing container, heat from the temperature control plate is stored in the processing container. On the other hand, when the lid is detached from the processing container and the processing container is open,
Since the heat in the processing chamber escapes to the outside of the processing chamber, the temperature in the processing chamber is high at the start of the processing, then gradually lowers, and the uniformity within the processing time cannot be maintained. Further, when the baking process on the wafer is started, the lid is detached from the processing container when the wafer is moved in and out. This affects the surface temperature of the wafer and adversely affects the pattern.

The present invention has been made based on these circumstances, and is intended to make the temperature distribution on the surface of the object in the process chamber uniform and to perform the process with high uniformity on the object. It is an object of the present invention to provide a substrate processing apparatus and a heat treatment method that can be performed.

Further, it has been confirmed by the inventor that when a plurality of workpieces are sequentially heat-treated in a mass production process of a semiconductor device or the like, the results of the heat treatment differ between the first few heat treatments and the subsequent heat treatments. . The present invention also aims to correct such a difference in the heat treatment result by a simple method and obtain a uniform treatment result.

[0009]

According to the present invention, there is provided a substrate processing apparatus provided with a baking apparatus for baking a substrate having a resist film selectively exposed by an exposure apparatus on a surface thereof, wherein the baking apparatus comprises: A main processing chamber for performing a baking process on the substrate, a sub-processing chamber provided adjacent to the main processing chamber via a door that can be opened and closed, and the substrate being subjected to the main processing chamber and the sub-processing. A substrate processing apparatus comprising a substrate transfer means for transferring a substrate to and from a chamber.

According to the present invention, the substrate processing apparatus is characterized in that the main processing chamber is connected to a pressure reducing means for reducing the pressure in the chamber.

According to the present invention, the main processing chamber is made of He.
A substrate processing apparatus characterized by heating in a gas atmosphere.

According to the present invention, the main processing chamber has a plurality of air holes formed in a temperature control plate serving as a heating plate.
The substrate processing apparatus is characterized in that hot air from the air hole flows between a front surface of the temperature control plate and a back surface of the substrate.

According to the invention, there is provided the substrate processing apparatus, wherein the main processing chamber supplies hot air also to the front surface side of the substrate.

According to the present invention, in a heat treatment method for sequentially performing heat treatment on a plurality of workpieces using a heat treatment apparatus having a temperature control plate and a cover that can be opened and closed, the step of opening the cover, With no object placed,
A step of closing the opened cover, a step of operating the temperature control plate for a predetermined time while the cover is closed to preheat the processing chamber, and performing the heat treatment after the preheating. Is the way.

It has also been confirmed that simply preheating the mixed control plate is not sufficient for the heat treatment effect for each object to be processed. According to the present invention, it is possible to obtain a uniform result to the extent that the first heat treatment has no effect.

Further, it is preferable that the predetermined time is made to coincide with a heat treatment time for one of the objects.
In this way, a uniform result can be obtained without special setting for preheating.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a plan view showing an entire system for coating and developing a semiconductor wafer (hereinafter, referred to as “wafer”) provided with a resist coating unit (COT) and a baking apparatus according to an embodiment of the present invention. .

In the coating and developing processing system 1, a plurality of wafers W as objects to be processed are loaded into and unloaded from the system in units of, for example, 25 wafers, for example, in units of 25 wafers. A cassette station 2 for loading and unloading, and a processing station 3 in which various single-wafer processing units for performing predetermined processing on the wafers W one by one in the coating and developing process are arranged at predetermined positions in multiple stages. An interface unit 5 for transferring a wafer W to and from an exposure apparatus 4 provided adjacent to the processing station 3 is integrally connected. In the cassette station 2, a plurality of wafer cassettes CR, for example, up to four wafer cassettes CR are provided at the positions of the positioning protrusions 7a on the cassette mounting table 7 with their respective wafer entrances facing the processing station 3 in the X direction (see FIG. 1). A wafer carrier 8 which is placed in a line (up and down direction) and is movable in the cassette arrangement direction (X direction) and the wafer arrangement direction (Z direction; vertical direction) of the wafers W clamped in the wafer cassette CR.
Selectively access each wafer cassette CR.

The wafer transfer member 8 is rotatable in the θ direction, and as will be described later, an alignment unit (ALIM) or an extension unit provided in a multi-stage unit of the third processing unit group G3 on the processing station 3 side. The unit (EXT) is formed so as to be accessible.

The processing station 3 is provided with a vertical transfer type main wafer transfer mechanism 9 having a wafer transfer device.
All the processing units are arranged in multiple stages around one or more sets around it.

FIG. 2 is a front view of the coating and developing processing system 1. In a first processing unit group G1, two spinner type processing units for performing a predetermined processing by placing a wafer W on a spin chuck in a cup CP. For example, a resist coating unit (COT) and a developing unit (DEV) are stacked in two stages from the bottom. Also, the second processing unit group G
2, two spinner type processing units, for example, a resist coating unit (COT) and a developing unit (DE)
V) are stacked in two stages from the bottom. These resist coating units (COT) are preferably arranged in the lower stage as described above because drainage of the resist solution is troublesome both mechanically and in terms of maintenance. However, it is of course possible to appropriately arrange the upper stage as needed.

FIG. 3 is a rear view of the coating and developing system 1.

In the main wafer transfer mechanism 9, the cylindrical support 11
The wafer transfer device 12 is mounted inside the inside of the device so as to be able to move up and down in the vertical direction (Z direction). The cylindrical support 11 is connected to a rotation shaft of a motor (not shown), and is rotated integrally with the wafer transfer device 12 about the rotation shaft by the rotation driving force of the motor, whereby the wafer transfer device is rotated. Reference numeral 12 is rotatable in the θ direction. The tubular support 11 may be configured to be connected to another rotating shaft (not shown) rotated by a motor. Further, the wafer transfer device 12 is provided with a plurality of holding members 14 movable in the front-rear direction of the transfer base 13, and these holding members 14 transfer the wafer W between the processing units. Making it possible.

As shown in FIG. 1, in the coating and developing processing system 1, five processing unit groups G1, G2,
G3, G4, and G5 can be arranged, and the multi-stage units of the first and second processing unit groups Gl and G2 are arranged on the system front (front side in FIG. 1) side, and the multi-stage units of the third processing unit group G3 are arranged. Throwing unit is Kasetoso station 2
, The multistage unit of the fourth processing unit group G4 can be arranged adjacent to the interface unit 5, and the multistage unit of the fifth processing unit group G5 can be arranged on the back side. .

As shown in FIG. 3, in the third processing unit group G3, an open type processing unit for performing a predetermined process by placing the wafer W on a holding table (not shown), for example, a cooling unit for performing a cooling process (COL), an adhesion unit (AD) for performing so-called hydrophobic treatment for improving the fixability of the resist, an alignment unit (ALIM) for positioning, an extension unit (EXT), and a heating process before the exposure process. A pre-baking unit (PREBAKE) for performing the heat treatment after the exposure processing, and a post-baking unit (Post E for performing the heat treatment after the exposure processing)
XposureBake Hereinafter, it is described as “PEB”. )
Are, for example, stacked in eight stages from the bottom. The fourth processing unit group G4 also includes open processing units, for example, a cooling unit (COL), an extension cooling unit (EXTCOL), an extension unit (EXT), and a cooling unit (C).
OL), Pre-baking unit (PREBAKE)
And post-baking units (PEB) are stacked in order from the bottom, for example, in eight stages.

As described above, the cooling unit (COL) and the extension cooling unit (EXTCOL) having a low processing temperature are arranged in the lower stage, and the pre-baking unit (PREBAKE) and the post-baking unit (PEB) having a high processing humidity are provided. ) And the adhesion unit (AD) in the upper stage, it is possible to reduce thermal mutual interference between the units. Of course, a random multi-stage arrangement can also be used.

As shown in FIG. 1, the interface unit 5
, The depth force direction (X direction) has the same dimensions as the processing station 3, but the width direction (Y direction) has a smaller size. A portable pickup cassette CR and a stationary buffer cassette BR are arranged in two stages on the front part of the interface part 5, while the exposure device 4 is arranged on the rear part, and furthermore, in the center part. Wafer carrier 16
Is provided. The wafer transfer body 16 moves in the X direction,
The cassettes CR and BR move in the Z direction and the exposure device 4
To access.

The wafer transfer body 16 is also rotatable in the θ direction, and includes an extension unit (EXT) provided in the multi-stage unit of the fourth processing unit group G4 on the processing station 3 side and an adjacent exposure apparatus. The wafer delivery table (not shown) on the fourth side can also be accessed.

In the coating and developing system 1, the multi-stage unit of the fifth processing unit group G5 shown by a broken line in FIG. 1 can be arranged on the back side of the main wafer transfer mechanism 9 as described above. The multi-stage units of the fifth processing unit group G5 are movable in the Y direction along the guide rails 17. Therefore, even when the multi-stage unit of the fifth processing unit group G5 is provided as shown in the drawing, the space is secured by moving along the guide rail 17, so that the main wafer transfer mechanism 9 can be moved. Maintenance work can be easily performed from behind.

Next, the resist coating unit (CO) included in the multistage unit of the first and second sets G1 and G2 is used.
T) will be described.

FIG. 4 is a schematic structural view of a resist coating unit (COT). The resist coating unit (COT) includes a coating device 21, a baking device 22, and a wafer transfer unit 23.
These are all controlled by the CPU 35. The wafer transfer section 23 is provided in a processing container 24 of the coating apparatus 21 which is partitioned from the atmosphere of the wafer transfer section 23.
A spin chuck 28 configured to rotate while holding the wafer W horizontally by vacuum suction, and a cup 29 surrounding the outer and lower sides of the spin chuck 28 and having a drain port 28a and an exhaust port 28b. And a coating liquid supply nozzle 30 that discharges a coating liquid supplied from a coating liquid supply device 31 connected to a coating liquid tank (not shown) to the surface of the wafer W held on the spin chuck 28. ing.

An opening 24a for loading / unloading the wafer W is provided on one side surface of the processing container 24.
a is configured to be opened and closed by a shutter 24b driven by cylinder driving means (not shown).
A spin chuck 28 is provided on the lower side of the processing container 24.
And a lifting means (not shown) for raising and lowering the spin chuck 28 is provided.

On the other hand, an air inlet 24c is provided in the ceiling of the processing vessel 24, and a filter (not shown) is arranged in the air inlet 24c, and air purified by the filter is supplied. It is configured to:
The coating liquid supply device 31 controls the temperature of the coating liquid supplied to the coating liquid supply nozzle 30 by a central processing unit (CPU) 3.
5 is provided with a coating liquid temperature controller (not shown) that adjusts (corrects) according to the control command given from 5.

The wafer transfer unit 23 has a drive unit 36 which is rotatable in the θ direction and movable in the Z axis direction.
3a is fixed. The wafer holding arm 23a holds the wafer W and moves in and out of an opening 24a for loading / unloading the wafer W provided on one side surface of the processing container 24. Similarly, the same operation is performed on the baking device 22.

As shown in FIG. 5, the baking apparatus 22 includes a main processing chamber 41 and a sub-processing chamber 42 which are formed adjacent to each other in the horizontal direction. A carrier 43 is provided. A temperature control plate 44, which is a heating means, is provided inside the main processing chamber 41, and a wafer is placed on the surface of the temperature control plate 44 for baking. The main processing chamber 41 and the sub processing chamber 42
A door 45 that can be opened and closed is provided at the boundary between the two. By closing the door 45, the main processing chamber 41 and the sub-processing chamber 42 are closed.
Is isolated so that there is no access to the interior atmosphere.

With these configurations, the wafer W processed by the coating apparatus 21 is carried into the wafer sub-processing chamber 42 by the wafer carrier 23. At this time, the main processing chamber 41 and the door 45 are closed, and the sub-processing chamber 42 is isolated so that the atmosphere does not enter or exit. After the transfer of the wafer W into the sub-processing chamber 42 is completed, the lid 51 of the sub-processing chamber 42 is closed so that the atmosphere does not enter or exit from outside the sub-processing chamber 42. Then, the door 45
Is opened, and is moved from the sub-processing chamber 42 to the main processing chamber 41 using the wafer transfer body 43, and is placed on the surface of the temperature control plate 44. The door 45 is closed, the main processing chamber 41 is sealed, and the chamber is set to a predetermined atmosphere, and the wafer W is baked. By performing the treatment in this manner, the flow of gas into and out of the main processing chamber 41 where the heat treatment is performed is reduced as much as possible.
1 can be reduced. Thereby, the inside of the main processing chamber 41 can be set and maintained at a favorable atmosphere.

Further, by maintaining the main processing chamber 41 at a vacuum or a low pressure by a connected pressure reducing means (not shown), the temperature change inside the main processing chamber 41 can be further reduced. In addition, when the inside of the main processing chamber 41 is sealed with a gas such as He having a small heat capacity, it is possible to heat the room more efficiently.

The wafer W that has been subjected to the predetermined baking process in the main processing chamber 41 is sequentially subjected to an operation reverse to the operation of inserting the wafer W into the main processing chamber 41, and is transferred from the wafer transfer section 23 to the transfer mechanism 9, and is transferred to the next step. Transferred to the processing room.

Next, a modification of the baking device 22 will be described. In the following modified examples, the basic configuration of the baking device 22 is the same, but the structure of the main processing chamber 41 is different. Therefore, only the structure of the main processing chamber 41 will be described.

FIG. 6 is a sectional view showing the structure of the main processing chamber 41a of the first modification. A temperature control plate 44a, which is a heating means, is provided inside the main processing chamber 41a, and the temperature control plate 44a has a plurality of through holes. These through holes are used as wafer support pin mounting holes 53a, 53b.
.. 53n and air holes 54a, 54b. The wafer support pins 56a, 56b... 56n implanted in the lever 55a of the pin drive mechanism 55 are freely inserted in the wafer support pin mounting holes 53a, 53b. Further, a plurality of positioning pins 59a, 59b,..., 59n, which are implanted and exposed in a lever 58a of a positioning pin driving mechanism 58 and are movable in the vertical direction, are disposed near the outer peripheral portion of the temperature control plate 44. The positioning pins 59a, 59b,.
4), an inclined surface is formed so as to approach the temperature control plate 44 as going downward. The pin driving mechanism 55 and the positioning pin driving mechanism 58 are both driven in the vertical direction by the cylinders 61a and 61b. On the other hand, the air holes 54a, 54b... 54n are connected to a blower (not shown). Note that a tank (not shown) for supplying a gas such as He set to a desired temperature is connected to the blower.

With these structures, the wafer is transferred to the sub-processing chamber 4.
The wafer is moved from 2 to the main processing chamber 41a using the wafer transfer body 43, is placed at a predetermined position on the surface of the temperature control plate 44a, closes the door 45, and seals the main processing chamber 41a. In this state, when the positioning pins 59a, 59b... 59n are raised, if the wafer W is placed at a position shifted from a predetermined position, the positioning pins 59a, 59b.
The end of the wafer W comes into contact with the 9n slope and is pressed toward the center of the temperature control plate 44a to be corrected to a predetermined position. Next, the wafer support pins 56a, 56b,... 56n are raised to raise the wafer W by a predetermined amount, and hold the wafer W above the temperature control plate 44a in a non-contact manner. In this state, when the blower is operated to blow gas such as He set to a predetermined temperature, each air hole 54 of the temperature control plate 44a is opened.
a, 54b... 54n spills on the lower surface of the wafer W and diffuses.
The gas during 4a is agitated to a substantially constant temperature. In this case, since the wafer W is not in contact with the temperature adjustment plate 44a, the temperature gradient of the temperature adjustment plate 44a is not directly received, and the in-plane temperature distribution of the wafer W can be made uniform by hot air.

Next, a second modification will be described. In this modification, a heating means is added to the first modification from above the wafer. FIG. 7 is a cross-sectional view illustrating a structure of a main processing chamber 41b according to a second modification. The same parts as those in FIG. 6 are denoted by the same reference numerals, and their description is omitted. In this case, the air holes 72a, 7a are also provided in the top plate 71 of the main processing chamber 41b.
2b... 72n are provided.
b ... 72n are connected to a blower (not shown). This blower is connected to a tank (not shown) for supplying a gas such as He set to a desired temperature. Therefore, a uniform temperature distribution is obtained on the lower surface side of the wafer W by hot air in the same manner as in the above-described first modification, and the upper surface side of the wafer W is also maintained on the upper surface of the wafer W at a desired temperature. By flowing hot air such as
The temperature change on the upper surface of the wafer W caused by radiant heat from the top plate 1b or the like can be suppressed.

Next, a modification of the baking apparatus of the present invention will be described. Embodiments described above (including modified examples)
Then, in any case, the baking device 22 includes the main processing chambers 41, 41.
a and 41b and the sub-processing chamber 42, but in this modification, it is formed only by the main processing chamber equipped with the temperature sensor.

FIG. 8 is a sectional view of the structure of the main processing chamber 75.
The main processing chamber 75 has temperature sensors 71, 71a,.
Are provided, and a cover 77 that can be opened and closed is also provided with cover temperature sensors 78, 78a,.
n is provided. Accordingly, the temperature of the temperature control plate 76 is controlled by the temperature sensor 7 mounted in the temperature control plate 76.
The control is performed using output values of 1, 71a... 71n. on the other hand,
In order to prevent radiant heat from the lid 77 or the like from affecting the temperature of the upper surface of the wafer W, the temperature is measured by cover temperature sensors 78, 78a,. Thereby, each temperature sensor 71, 71a ... 71n, 78,
When the value of 78a... 78n is within the specified range, the processing is started. As a result, it is possible to prevent the temperature of the wafer W during the baking process from changing for each wafer W.

FIG. 9A shown in the section of the prior art.
Also in the processing apparatus having the structure shown in FIGS. 9A and 9B, before starting the baking process on the wafer W, the baking process operation is performed several times without inserting the wafer W into the processing container 91. Is performed, the state inside the processing container 91 is changed to the state at the time of continuous processing, and the state is maintained, and the wafer W is transferred to the temperature control plate 9 inside the processing container 91.
2 and subjected to baking processing, the wafer W
Can be subjected to predetermined high uniformity processing.

The temperature control of the present invention can be applied not only to the developing and coating apparatus illustrated in the above embodiments, but also to an apparatus requiring uniform temperature control in the processing chamber. For example, in an ashing apparatus, the peeling rate of a film changes when the temperature in the processing chamber changes. Therefore, by keeping the temperature constant, the amount of film peeling for each substrate such as a wafer can be made constant. Further, in the film forming apparatus, the amount of increase in film thickness per time is different when the temperature in the processing chamber is changed. Therefore, by keeping the temperature in the processing chamber constant, the film thickness can be controlled by time management. Similarly, when applied to an etching apparatus, it is possible to control the film thickness by etching.

In the case where heat treatment of a plurality of semiconductor substrates is sequentially performed in a mass production process of a semiconductor device or the like, the maximum width of the line width after the baking process is different between the first heat treatment and the stable heat treatment. It has been found that a non-negligible error of about 10 to several nm occurs. In order to solve this problem, it is desirable to preheat the temperature control plate and open and close the cover before starting the heat treatment. This makes it possible to perform preheating under conditions close to those of the actual heat treatment. It is further desirable that the operation time of the temperature control plate in the preheating is made to coincide with the time of the heat treatment.

Further, an operation having the same heat dissipation effect as the above operation may be performed. In this way, a more uniform result can be obtained without special setting for preheating. The heat treatment may be performed after repeating such a preheating operation several times. By performing the same operation in a state where the substrate is not placed, the uniformity of processing for each substrate can be easily increased.

As described above, according to the present invention, since the temperature change in the processing chamber can be reduced, the in-plane temperature uniformity of the object to be processed such as a wafer can be improved. Thereby, the pattern dimension variation in the plane of the object to be processed can be reduced. At the same time, it is possible to reduce variation in pattern size between workpieces such as wafers for each lot.

[0051]

According to the present invention, the temperature distribution of the object in the processing chamber can be made uniform, and the object to be processed can be processed with high uniformity.

[Brief description of the drawings]

FIG. 1 is a plan view of an entire coating and developing system of the present invention.

FIG. 2 is a front view of the coating and developing treatment system of the present invention.

FIG. 3 is a rear view of the coating and developing system of the present invention.

FIG. 4 is a schematic configuration diagram of a resist coating unit (COT).

FIG. 5 is a configuration diagram of a baking apparatus of the present invention.

FIG. 6 is a sectional view of a modification of the main processing chamber of the baking apparatus of the present invention.

FIG. 7 is a cross-sectional view of another modification of the main processing chamber of the baking apparatus of the present invention.

FIG. 8 is a sectional view of another modification of the main processing chamber of the baking apparatus of the present invention.

FIGS. 9A and 9B are cross-sectional views illustrating the configuration of the baking processing chamber during operation.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 coating / developing processing system, 2 cassette station, 3 processing station, 4 exposure apparatus, 5 interface unit, 21 coating apparatus, 22 baking apparatus
24: processing container, 41, 41a, 41b: main processing chamber, 4
2 ... sub-processing chamber, 44 ... temperature control plate, 45 ... door, 54
a, 54b to 54n: air holes, 74a, 74b to 74n
… Temperature sensor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Daizo Muto 800 Yamano Isshiki-cho, Yokkaichi-shi, Mie F-term in Toshiba Yokkaichi Plant (reference) JA01 JA17 JA46 KA03 KA11 MA02 MA03 MA06 MA11 MA27 MA30 NA04 NA05 NA07 PA11 PA30 5F046 CD01 CD05 KA04 KA05 KA07

Claims (7)

[Claims] 1. A substrate processing apparatus comprising a baking device for baking a substrate having a resist film selectively exposed by an exposure device on a surface thereof, wherein the baking device performs a baking process on the substrate. A main processing chamber, a sub-processing chamber provided adjacent to the main processing chamber via a door that can be opened and closed, and a substrate transfer unit that transfers the substrate between the main processing chamber and the sub-processing chamber. A substrate processing apparatus comprising: 2. The substrate processing apparatus according to claim 1, wherein said main processing chamber is connected to a pressure reducing means for reducing the pressure in the chamber. 3. The substrate processing apparatus according to claim 1, wherein the main processing chamber is heated in a He gas atmosphere. 4. The main processing chamber has a plurality of air holes formed in a temperature control plate as a heating plate, and hot air from the air holes is provided between a front surface of the temperature control plate and a back surface of the substrate. The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus is formed so as to flow. 5. The substrate processing apparatus according to claim 4, wherein said main processing chamber supplies hot air also to a surface side of said substrate. 6. A heat treatment method for sequentially performing heat treatment on a plurality of workpieces using a heat treatment apparatus having a temperature control plate and a cover that can be opened and closed, wherein: the step of opening the cover; and the step of not placing the workpiece. A step of closing the opened cover in the state, a step of operating the temperature control plate for a predetermined time while the cover is closed to preheat the processing chamber, and performing the heat treatment after the preheating. Heat treatment method. 7. The heat treatment according to claim 6, wherein the predetermined time is equal to a time of heat treatment for one of the objects to be processed, or an operation having a heat dissipation effect similar to the operation is performed. Method.