TWI740570B - Substrate heat treatment furnace - Google Patents

Abstract

The invention discloses a substrate heat treatment furnace. The present invention may include: a heat treatment furnace with at least one furnace door on the front side and at least one shutter on the back side, so that the substrate can be put into the preset space in the chamber or the substrate after the heat treatment process is removed from the chamber; and a bearing shaft The guide element for moving up and down in the horizontal direction along both sides of the furnace door has a track that induces the shaft of the bearing to move up and down in the form of shaft coupling, and is arranged along the vertical direction on both sides of the furnace door. A furnace door operating mechanism is provided to guide the furnace door to move up and down; and a furnace door operating mechanism having a movable cylinder combined with the side surface of the furnace door to open and close the furnace door to move up and down along the vertical movement track.

Description

Substrate heat treatment furnace

The present invention relates to a heat treatment furnace for heat treatment of flat panel displays, and more specifically, to a substrate heat treatment furnace for improving the door, shutter and sealing performance of the heat treatment furnace.

Organic light-emitting display devices and LCD glass substrates (hereinafter referred to as flat panel displays) are used in various image devices such as image screens, TVs, mobile phones, and displays. Organic light-emitting display devices and LCD glass substrates are used in various fields as one of the next-generation displays. Recently, in order to improve performance and yield, the development of flat panel display manufacturing technology in this field has been continuously carried out.

In the process of manufacturing typical flat panel displays, organic light-emitting display devices or LCD glass substrates (hereinafter referred to as substrates or glass substrates), temperature control and temperature uniformity are essential to ensure high-quality substrate quality and yield.

For example, in the manufacturing process of an organic light-emitting display device, since the organic layer is formed on the surface of the substrate, a certain amount of water may be contained, so a drying process for evaporating the water is required.

In the LCD glass substrate manufacturing process, a cleaning process is performed before the photosensitive film is coated on the surface of the substrate, and a heating and drying process for removing moisture is performed after the cleaning process.

In addition, after the photosensitive film is coated on the LCD glass substrate, the exposure and development process is performed sequence. The pre-baking and post-baking processes are sequentially performed before and after the exposure and development process.

In this way, the substrate manufacturing process performs heating and drying processes to manufacture the substrate. The moisture generated in the substrate manufacturing process can be removed by ultraviolet rays or by putting it into the chamber of a heat treatment furnace that includes heating elements such as a heater (sheath heater) and then heating and drying it.

Korean Patent Publication No. 10-2094763 has proposed a heat treatment furnace for substrates related to this.

In order to heat the flat panel display substrate through the chamber of the heat treatment furnace, the conditions required for each process are different. In order to meet all these conditions, only by preventing the influence of external air on the chamber and minimizing the heat loss to the outside of the chamber, can the heat treatment performance of the substrate be prevented from degrading, and it can meet the requirement of reducing the product defect rate in a single process. Process conditions.

In addition, in order to increase the yield of finished products through heat treatment in the heat treatment furnace, there is an increasing demand for high performance heat treatment furnaces. This is because the smaller the deviation within the substrate, the better, but the conventional heat treatment furnaces cannot meet this requirement.

On the other hand, in the process before and after the substrate is subjected to heat treatment in the heat treatment furnace, in order to put the substrate into the chamber or carry out the substrate after the heat treatment, while preventing the external air from flowing into the chamber and preventing the process gas from the chamber from being discharged, The heat treatment furnace includes a furnace door and a shutter.

Regarding the door and shutter of the heat treatment furnace, the shutter device of the heat treatment furnace has been proposed in the Korean Patent Publication No. 10-1663262, and the shutter drive device of the glass heat treatment furnace has been proposed in the Korean Patent Publication No. 10-1327920.

For example, conventional furnace doors and shutters of heat treatment furnaces have been proposed in the form of setting the furnace door outside the chamber and opening and closing it left and right, using a handle to open and closing the door, or fixing it with bolts.

However, the opening and closing form of the chamber door of the conventional heat treatment furnace is not only complicated to operate, but also causes heat loss in the chamber. That is, because the furnace door and the surface of the chamber are not evenly adhered, the heat of the chamber is discharged through the gap or the external air flows into the chamber to generate heat loss, so it is impossible to provide sealing performance through the close contact between the furnace door and the chamber. .

Therefore, there is a need for a substrate heat treatment furnace that can ensure the sealing structure of the furnace door and the shutter suitable for the heat treatment furnace chamber and the sealing performance that meets the high-temperature configuration.

Therefore, the inventor of the present application proposes a high-performance substrate heat treatment furnace, which uses cylinders and bearings to open and close the furnace door in the form of left and right switches, and uses brackets and seals to make the furnace door and the chamber closely adhere to each other. Ensure the sealing performance, thereby reducing the heat loss in the chamber.

A technical problem solved by the present invention is to change the opening and closing mode of the furnace door of the heat treatment furnace to the up and down opening and closing operation mode, so as to provide the operation stability and the effectiveness of the installation space.

Another technical problem solved by the present invention is to minimize the heat loss of the chamber by ensuring the sealing structure of the furnace door and the shutter suitable for the heat treatment furnace chamber and the sealing performance in accordance with the high-temperature configuration.

In order to achieve the above-mentioned object, the substrate heat treatment furnace according to the present invention may include: a heat treatment furnace having at least one furnace door on the front side and at least one shutter on the back side to put the substrate into the preset space in the chamber or from the chamber Carry out the substrate after the heat treatment process; bearing axis, which protrudes horizontally along both sides of the furnace door; up and down movement guides, which have an up and down movement track that induces the bearing axis in the form of shaft coupling, and The two sides of the furnace door are arranged along the vertical direction to guide the furnace door to move up and down; and the furnace door operating mechanism part has a movable steam combined with the side surface of the furnace door A cylinder to open and close the furnace door to move up and down along the up-and-down moving rail.

According to an embodiment of the present invention, the bearing axis may be combined with the bearing axis mounting block of the furnace door.

According to an embodiment of the present invention, a support bracket is provided on the furnace door, the support bracket may have a handle for close contact with the furnace door, and a moving screw is combined with the handle for close contact with the furnace door, which rotates on the outside. The moving screw makes the furnace door close to the chamber side.

According to an embodiment of the present invention, a silicon sealing member may be sandwiched between the furnace door and the chamber.

According to an embodiment of the present invention, the silicon sealing member may have an elastic deformation space formed biased toward the outside of the furnace door.

According to an embodiment of the present invention, a silicon sealing member may be sandwiched between the shutter and the chamber.

According to an embodiment of the present invention, the silicon sealing member may have an elastic deformation space that is formed biased toward the outside of the shutter.

According to an embodiment of the present invention, the peripheral portion of the silicon sealing member includes a cooling pipe for preventing the cooling of the silicon sealing member for sealing from causing a decrease in sealing performance caused by hardening.

According to an embodiment of the present invention, the shutter may have a plurality of shielding plates for shielding heat discharged from the inside of the chamber to the outside.

According to an embodiment of the present invention, the shielding plate may be composed of an inner shielding plate opposite to the cavity, an intermediate shielding plate arranged at a position spaced apart from the inner shielding plate, and a position spaced apart from the intermediate shielding plate. It is composed of upper and outer side shielding plates.

According to an embodiment of the present invention, there is a cooling system that allows cooling water to flow through the intermediate shielding plate. Cool down to make the surrounding temperature drop.

The substrate heat treatment furnace according to the present invention has the following effects: by changing the opening and closing method of the furnace door of the heat treatment furnace to the cylinder-based up and down opening and closing operation method, compared with the left and right opening opening and closing method, unnecessary space is minimized, Therefore, it is possible to fully ensure ample space for the installation of the heat treatment furnace, and to improve the operation stability of the furnace door switch.

The substrate heat treatment furnace according to the present invention has the effect of minimizing the heat loss of the chamber by ensuring the sealing structure of the furnace door and the shutter suitable for the heat treatment furnace chamber and the sealing performance in accordance with the high-temperature configuration.

100: Heat treatment furnace

110: Chamber

121: Support

120: Frame

200: furnace door

210: Bearing axis

220: Move the guide up and down

230: Move the track up and down

240: Bearing shaft mounting block

250: Handle for close contact with furnace door

251: moving screw

260: Support bracket

300: occluder

310: Shield plate

311: inner shielding plate

312: Intermediate shielding plate

313: Outer shield plate

320: cooling pipe

400: Furnace door operating mechanism department

410: Movable cylinder

420: Movable lever

500: Silicon sealing parts

510: Elastic Deformation Space

520: cooling pipe

Fig. 1 shows an example of the front side of a substrate heat treatment furnace according to an embodiment of the present invention.

Fig. 2 shows an example of the rear side of a substrate heat treatment furnace according to an embodiment of the present invention.

Fig. 3 shows an example of the front of a substrate heat treatment furnace according to an embodiment of the present invention.

Fig. 4 is an example of a cross-sectional view taken along line A-A in Fig. 3.

FIG. 5 is an example of extracting and displaying the upper and lower operation parts of the furnace door of the substrate heat treatment furnace according to an embodiment of the present invention.

FIG. 6 is an example of excerpting and displaying the guide part of the furnace door of the substrate heat treatment furnace according to an embodiment of the present invention, which moves up and down.

Fig. 7 is an example of an excerpt from part C of Fig. 4 and Fig. 6 together with a cross-sectional view and a concrete display example.

Fig. 8 is an example of an excerpt from part D of Fig. 4 and a cross-sectional view for concrete display.

Figure 9 is a diagram showing a silicon seal used to prevent the chamber and the shutter according to an embodiment of the present invention An example of a cooling unit for thermal hardening of the sealing part.

Fig. 10 shows an example of a cooling unit provided on the shutter according to an embodiment of the present invention.

Hereinafter, the content of the substrate heat treatment furnace according to the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Generally, in order to put the substrate to be heat-treated into each preset stage in the chamber or to remove the substrate after the heat treatment process from the chamber, the front side and the back side of the heat treatment furnace for heat-treating the substrate may have furnace doors and shutters respectively.

The furnace door and shutter of the heat treatment furnace need to meet the following conditions: the heat treatment process is a sealed structure; there is no problem when used at high temperatures; there is no interference and safety when the furnace door is opened and closed.

In addition, when manufacturing the substrate heat treatment furnace, although the basic configuration of the device can be selected from among them, what is important is the high-performance sealing structure that can minimize the heat loss in the chamber during the heat treatment process.

However, the conventional heat treatment furnace door installation form, such as the form of setting the furnace door outside the chamber and opening and closing by sliding left and right; the form of using a handle to switch left and right; or the form of fixing with bolts, so it is not only open and close. It is complicated and needs to ensure sufficient space for opening and closing the furnace door, there are restrictions on the layout space, and the heat loss in the chamber cannot be fully controlled.

That is, because the furnace door and the cavity surface are not evenly attached, the heat of the cavity is discharged through the gap or the external air flows into the cavity to cause heat loss, so it is impossible to provide sealing performance through the close contact between the furnace door and the cavity. .

Therefore, the present invention changes the left and right opening and closing method of the furnace door of the conventional heat treatment furnace to the up and down opening and closing method based on the cylinder and the bearing, and proposes a furnace door operation stability and installation space efficiency. Heat treatment furnace.

On the other hand, the present invention uses a bracket to close the furnace door 200 to the chamber 110 and ensures the sealing structure of the furnace door 200 and the shutter 300 suitable for the chamber 110 of the heat treatment furnace 100 and the sealing performance in accordance with the high-temperature configuration. The heat loss of the chamber 110 can be minimized in the heat treatment furnace 100.

That is, the present invention utilizes cylinders and bearings to open and close the furnace door 200 up and down, and uses a bracket to make the furnace door 200 closely adhere to the chamber 110 to provide a high-performance heat treatment furnace 100.

Hereinafter, the detailed content of the preferred embodiment according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an example of the front side of a substrate heat treatment furnace 100 according to an embodiment of the present invention. FIG. 2 shows an example of the rear side of the substrate heat treatment furnace 100 according to an embodiment of the present invention. FIG. 3 shows an example of the front surface of a substrate heat treatment furnace 100 according to an embodiment of the present invention.

As shown in Figures 1 to 3, the heat treatment furnace 100 has a chamber 110 formed with an input port through which a substrate (not shown) to be heated or dried can pass through. The heater is composed of a heater, and the substrate is heated by the heat generated by the heater or dried by evaporating water. Moreover, the upper and lower parts of the heater can be closely provided with upper/lower heat transfer plates.

One side of the chamber 110 of the heat treatment furnace 100 is provided with an air supply port for the fluid containing process gas to flow in, and an exhaust port for discharging the fluid in the chamber 110, and may include a chamber 110 for supporting and holding up the chamber 110. The frames 120 of the plurality of supports 121 and the conductive parts connected to the plurality of bus bars are connected to the heating wires of the heater to conduct current.

On the other hand, referring to Figures 1 to 3, the basic components that make up the heat treatment furnace 100, such as the heater, the upper/lower heat transfer plate, the process gas supply and exhaust system, and the conductive part including the power supply to the heater The power supply system is not directly related to the present invention. And the heat treatment furnace 100 The basic components have nothing to do with the gist of the present invention and are known components, so these components are omitted in the drawings of the present invention.

As shown in FIGS. 1 to 3, the substrate heat treatment furnace 100 according to the present invention has at least one furnace door 200 on the front side and at least one shutter 300 on the back side, so that the substrate to be heat treated is placed in each preset in the chamber 110. The stage part or the substrate after the heat treatment process is carried out from the chamber 110.

The main configuration of the substrate heat treatment furnace 100 according to the present invention is shown in FIGS. 4 to 8.

Fig. 4 is an example of a cross-sectional view taken along line A-A in Fig. 3. FIG. 5 is an example of extracting and displaying the upper and lower operation parts of the furnace door of the substrate heat treatment furnace according to an embodiment of the present invention. FIG. 6 is an example of excerpting and displaying the guide part of the furnace door of the substrate heat treatment furnace according to an embodiment of the present invention, which moves up and down. Fig. 7 is an example of an excerpt from part C of Fig. 4 and Fig. 6 together with a cross-sectional view and a concrete display example. Fig. 8 is an example of an excerpt from part D of Fig. 4 and a cross-sectional view for concrete display.

The substrate heat treatment furnace 100 according to the present invention has a bearing shaft 210 protruding horizontally along both sides of the furnace door 200.

Moreover, it has a vertical movement guide 220. The up and down movement guide 220 has a rail 230 that induces the bearing shaft 210 to move up and down in the form of shaft coupling, and is arranged on both sides of the furnace door 200 in a vertical direction to guide the furnace door 200 to move up and down.

On the other hand, the furnace door operating mechanism part 400 may be included. The furnace door operating mechanism part 400 has a movable cylinder 410 combined with the side surface of the furnace door 200 to move the furnace door 200 up and down along the vertical moving rail 230 to open and close.

In addition, the bearing shaft 210 can be combined with the bearing shaft mounting block 240 of the furnace door 200.

On the other hand, the furnace door 200 is provided with a support bracket 260, and the support bracket 260 is provided with a handle 250 for close contact with the furnace door, and a moving screw is combined with the handle 250 for close contact with the furnace door. 251. Rotate the moving screw 251 outside to make the furnace door 200 close to the chamber 110 side.

In addition, a silicon sealing member 500 is sandwiched between the furnace door 200 and the chamber 110 to keep the contact surface between the furnace door 200 and the chamber 110 in a tightly sealed state, so that the heat in the chamber 110 can be controlled not to the outside discharge.

Moreover, a silicon sealing member 500 is sandwiched between the shutter 300 and the chamber 110 to keep the contact surface between the shutter 300 and the chamber 110 in a tightly sealed state, so that the heat in the chamber 110 can be controlled to prevent Drain to the outside.

In addition, the silicon sealing member 500 has an elastic deformation space 510 that is heavily formed toward the outside of the furnace door 200.

Therefore, when the furnace door 200 is closed, the elastic deformation space 510 of the silicon sealing member 500 is first deformed when the furnace door 200 is closed, and the gap between the contact surface of the furnace door 200 and the chamber 110 is blocked to form a tight joint The contact surface in the state of the furnace door 200 maintains airtightness between the contact surface of the chamber 110.

On the other hand, the silicon sealing member 500 may have an elastic deformation space 510 that is heavily formed toward the outside of the shutter 300.

Therefore, when the shutter 300 is closed, the elastic deformation space 510 of the silicon sealing member 500 deforms first while closing the shutter 300, and blocks the gap between the contact surface of the shutter 300 and the cavity 110 to form a tight contact The contact surface of the state can maintain the airtightness between the contact surface of the shutter 300 and the cavity 110.

Among them, the silicon sealing member 500 serves as a sealing member sandwiched between the chamber 110 and the side of the furnace door 200 and the side of the shutter 300, and can exhibit expected performance. It can be better selected to have sufficient tensile force and elasticity compared to the silicon sealing component 500, the chamber 110 and the surrounding structures, and at the same time, under the high temperature configuration Seals that still have durable physical properties.

As shown in FIGS. 9 and 10, the substrate heat treatment furnace according to the embodiment of the present invention may include a cooling unit.

FIG. 9 shows an example of a cooling unit for preventing thermal hardening of the silicon sealing member 500 provided on the chamber 110 and the shutter 300 according to an embodiment of the present invention.

As shown in FIG. 9, the peripheral portion of the silicon sealing member 500 is preferably provided with a cooling pipe 520. Although FIG. 9 is an example for explaining the cooling structure of the silicon sealing member 500 provided on the side of the shutter 300, a cooling unit may be provided on the side of the furnace door 200 with the same principle and structure.

Thus, by cooling the sealing silicon sealing member 500 provided on the side of each furnace door 200 and the side of the shutter 300, it is possible to effectively prevent the deterioration of the sealing performance caused by hardening.

FIG. 10 shows an example of the cooling unit provided on the shutter 300 according to an embodiment of the present invention.

As shown in FIG. 10, the shutter 300 may preferably have a plurality of shielding plates 310 for shielding the heat discharged from the inside of the chamber 110 to the outside.

The shielding plate 310 may preferably be composed of an inner shielding plate 311 opposite to the chamber 110, a middle shielding plate 312 arranged at a position spaced apart from the inner shielding plate 311, and an outer shielding plate arranged at a position spaced apart from the intermediate shielding plate 312. 313 composition.

Furthermore, there may be a cooling pipe 320 in which cooling water flows based on the middle shielding plate 312.

As a result, the peripheral temperature of the shutter 300 can be lowered, and the sealing performance can be prevented from being degraded by preventing thermal hardening of the silicon sealing member 500 provided on the periphery, thereby maintaining stable sealing performance.

Hereinafter, the operation of the substrate heat treatment furnace 100 according to the present invention will be described with reference to FIGS. 4 to 8.

First, for the operation of opening the furnace door 200, if the movable cylinder 410 of the furnace door operating mechanism part 400 is operated, the movable rod 420 of the movable cylinder 410 pushes the furnace door 200 upward.

At this time, the bearing shaft 210 protruding from the furnace door 200 moves upward along the up-and-down moving rail 230 of the up-and-down movement guide 220. If the movable cylinder 410 stops operating, the furnace door 200 remains open at the current position.

Next, for the operation of closing the furnace door 200, if the movable cylinder 410 of the furnace door operating mechanism 400 is operated to return the movable rod 420 of the movable cylinder 410 to the original position, the furnace door 200 is pulled toward the original position.

At this time, the bearing shaft 210 protruding from the furnace door 200 moves down along the up-and-down moving rail 230 of the up-and-down movement guide 220. If the movable cylinder 410 stops operating, the furnace door 200 remains closed at the current position.

Among them, the bearing shaft 210 is combined with the bearing shaft mounting block 240 of the furnace door 200, so it will not be damaged, and the furnace door 200 can be opened and closed safely and smoothly.

On the other hand, a support bracket 260 is provided on the furnace door 200, and the support bracket 260 may be provided with a handle 250 for close contact with the furnace door. The screw 251 is moved so that the furnace door 200 is in close contact with the chamber 110 side.

If the handle 250 for close contact with the furnace door is rotated by hand, the moving screw 251 moves in a linear direction along with the support bracket 260 and moves the furnace door 200 to be close to the contact surface of the chamber 110.

Therefore, the warpage or gap between the contact corresponding surfaces of the furnace door 200 and the cavity 110 is reduced, thereby maintaining a close contact state.

In addition, a silicon sealing member 500 is interposed between the furnace door 200 and the chamber 110. If closed For the furnace door 200, the silicon sealing component 500 keeps the contact surface between the furnace door 200 and the chamber 110 in a tightly sealed state, thereby controlling the heat in the chamber 110 not to be discharged to the outside of the furnace door 200.

In addition, a silicon sealing member 500 is interposed between the shutter 300 and the chamber 110. If the shutter 300 is closed, the silicon sealing member 500 keeps the contact surface between the shutter 300 and the chamber 110 in a tightly sealed state, thereby It plays a role of controlling the heat in the chamber 110 not to be discharged to the outside of the shutter 300.

Therefore, when the furnace door 200 and the shutter 300 are closed, the elastic deformation space 510 of the silicon sealing member 500 deforms first while closing the furnace door 200 and the shutter 300, and blocks the cavities of the furnace door 200 and the shutter 300 The gap between the contact surfaces of the chamber 110 forms a contact surface in a tightly connected state, so that the contact surface between the shutter 300 and the chamber 110 is kept airtight.

According to the heat treatment furnace 100 of the present invention, the sealing structure can be effectively maintained during the heat treatment process, and there is no problem when used at high temperatures, and the upper and lower operation range of the furnace door 200 does not exceed the body area occupied by the overall heat treatment furnace 100, so the furnace door 200 operation process There is no interference caused by the installation space. Moreover, the furnace door 200 can be opened and closed by the movable cylinder 410, thereby improving the work safety.

The substrate heat treatment furnace 100 according to the present invention has the following effects: by changing the opening and closing method of the furnace door 200 of the heat treatment furnace 100 to a cylinder-based up and down opening and closing operation method, compared with the left and right opening opening and closing method, unnecessary space is saved. Minimization, therefore, sufficient space for the installation of the heat treatment furnace 100 can be ensured, and the operation stability of the opening and closing of the furnace door 200 can be improved.

The substrate heat treatment furnace 100 according to the present invention has the effect of minimizing the heat loss of the chamber 110 by ensuring a sealing structure suitable for the furnace door 200 and the shutter 300 of the chamber 110 of the heat treatment furnace 100 and the sealing performance in accordance with the high-temperature configuration.

Although the present invention is described with reference to an embodiment illustrated in the drawings, the present invention does not Not limited to these embodiments, modifications and variations can be made within the scope not departing from the gist of the present invention, and these modifications and variations belong to the technical idea of the present invention.

110: Chamber

200: furnace door

210: Bearing axis

220: Move the guide up and down

230: Move the track up and down

250: Handle for close contact with furnace door

251: moving screw

260: Support bracket

410: Movable cylinder

Claims (8)

A substrate heat treatment furnace, comprising: a heat treatment furnace with at least one furnace door on the front side and at least one shutter on the back side, so that the substrate is put into the preset space in the chamber or the substrate after the heat treatment process is removed from the chamber; The bearing shaft protrudes horizontally along both sides of the furnace door; the up-and-down moving guide has a track that induces the bearing shaft to move up and down in the form of shaft coupling, and runs along both sides of the furnace door. A vertical direction is provided to guide the furnace door to move up and down; and a furnace door operating mechanism part, which has a movable cylinder combined with the side of the furnace door, so that the furnace door moves up and down along the vertical movement rail to open and close Wherein, the furnace door is provided with a support bracket, the support bracket has a handle for close contact with the furnace door, the handle for close contact with the furnace door is combined with a moving screw, and the moving screw is rotated outside to make the furnace The door is in close contact with the chamber; wherein, a sealing member is interposed between the furnace door and the chamber, and the sealing member has an elastic deformation space that is formed biased toward the outside of the furnace door; wherein, the Another sealing member is sandwiched between the shutter and the cavity, and the other sealing member has an elastic deformation space that is formed biased toward the outside of the shutter. The substrate heat treatment furnace according to claim 1, wherein the bearing shaft is combined with the bearing shaft installation block of the furnace door. The substrate heat treatment furnace according to claim 1, wherein the sealing member is a silicon sealing member. The substrate heat treatment furnace according to claim 1, wherein the other sealing member is a silicon sealing member. The substrate heat treatment furnace according to claim 3 or 4, wherein the peripheral portion of the silicon sealing member includes a cooling pipe for preventing the cooling of the silicon sealing member for sealing from causing deterioration of sealing performance caused by hardening. The substrate heat treatment furnace according to claim 1, wherein the shutter has a plurality of shielding plates for shielding heat discharged from the inside to the outside of the chamber. The substrate heat treatment furnace according to claim 6, wherein the shielding plate is composed of an inner shielding plate opposite to the chamber, an intermediate shielding plate arranged at a position separated from the inner shielding plate, and an intermediate shielding plate arranged on the inner shield plate. It is composed of the outer shielding board at the position separated by the board. The substrate heat treatment furnace according to claim 7, which has a cooling pipe that allows cooling water to flow through the intermediate shielding plate to lower the temperature of the periphery.

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