TWI400418B - Heat treatment apparatus and heat treatment method - Google Patents

Description

Heat treatment device and heat treatment method

The present invention relates to a heat treatment apparatus and a heat treatment method.

Patent Document 1 discloses a method in which a pressure in a processing chamber is equal to or higher than atmospheric pressure, and a heater provided in a position near a periphery of a workpiece to be processed is heated to heat a workpiece.

Patent Document 1: Japanese Patent No. 2622356

In the case of heat treatment of a workpiece using a heater, when the object to be heat-treated is a particularly large substrate, there is a case where a large temperature difference occurs in the surface of the substrate due to uneven heating to cause breakage.

Further, in Patent Document 1, although a gas flow is generated in the heating chamber by the fan, this does not necessarily apply to the surface to be processed of the workpiece uniformly, or the airflow is not heated, so that it is not sufficient to uniformly heat the surface to be treated of the workpiece.

The present invention has been made in view of the above problems, and provides a heat treatment apparatus and a heat treatment method so that even a large substrate can be uniformly heat-treated without unevenness in the plane.

According to an aspect of the present invention, a heat treatment apparatus comprising: a sealed container that can be sealed with respect to the atmosphere; a processing space that can accommodate a substrate in the sealed container; and the treatment in the sealed container; a heater opposite to the space; and a showerhead having an introduction phase a gas introduction hole that is inert to the substrate and that heats or cools the gas of the substrate, and a gas that is disposed opposite to the substrate and that blows the gas introduced into the substrate through the gas introduction hole toward the substrate a hole is blown out, and the shower head is disposed in the sealed container; and a dispersing plate that separates an upstream chamber on the gas introduction hole side from a downstream chamber on the gas blowing hole side is provided in the shower head; Forming, on the dispersing plate, a plurality of through holes for communicating the upstream chamber and the downstream chamber; a total area of all openings of the plurality of gas blowing holes is larger than a total area of all openings of the plurality of through holes; In the interior of the shower head into which the gas is introduced, the pressure of the upstream chamber is higher than the pressure of the downstream chamber; and the gas system is blown out from the gas blowing hole with respect to the processing space that has been decompressed, and the treatment is performed The aforementioned gas is replaced in space.

Further, according to another aspect of the present invention, a heat treatment method is provided which decompresses a processing space in which a substrate is housed, and after the depressurization, a heater disposed opposite to the processing space Heating the substrate; after the substrate or the processing space reaches a desired temperature by heating by the heater, the gas that is inert to the substrate and heated is sprayed from the opposite side of the substrate The head is blown to the substrate to heat the substrate; the upstream side and the downstream side of the inside of the shower head are partitioned into a plurality of spaces by a dispersion plate, and the gas system introduced into the shower head is in the plural The space diffuses and gradually pushes toward the downstream side, causing the pressure to slowly drop.

According to the present invention, it is possible to provide a heat treatment apparatus and a heat treatment method in which a large-sized substrate can be uniformly heat-treated in a plane without unevenness.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a schematic view showing the configuration of a main part of a heat treatment apparatus according to an embodiment of the present invention.

The heat treatment apparatus according to the embodiment of the present invention has a structure in which an upper heater 21, a lower heater 22, and a shower head 10 are provided in a sealed container 1 capable of maintaining a sealed atmosphere with respect to the atmosphere. The upper heater 21 and the lower heater 22 are sheath heaters or lamp heaters that hold a heating wire, for example, in a metal pipe. The upper heater 21 and the lower heater 22 are disposed opposite to each other, and the processing space 20 is formed between the upper heaters 22.

A cover 23 surrounding the periphery of the processing space 20 is provided, and a cover 24 surrounding the periphery of the processing space 20 is provided. One of the upper cover 23 and the lower cover 24 is partially opened to form the carry-out port 25 of the substrate 5. The substrate 5 to be processed is carried into the processing space 20 via the carry-out port 25 .

The shower head 10 is disposed above the upper heater 21. An exhaust port 26 is provided below the lower heater 22. An exhaust system such as a vacuum pump (not shown) is connected to the exhaust port 26, and the inside of the sealed container 1 including the processing space 20 is exhausted through the exhaust port 26. Further, the gas blown from the shower head 10 is also exhausted from the processing space 20 through the exhaust port 26. The exhaust port 26 is preferably located below the lower heater 22 in consideration of the flow of the gas blown from the shower head 10 to the substrate 5.

Hereinafter, the details of the shower head 10 will be described.

Fig. 2 is a perspective view of the shower head 10 as seen from the lower side.

3 is a cross-sectional view of the shower head 10, and FIG. 4 is an enlarged view of the main part of FIG.

The shower head 10 is formed in a square block shape having a planar size close to the area of the substrate 5 to be processed, and as shown in FIG. 3, the upstream chamber 13 and the downstream chamber 14 partitioned by the dispersion plate 17 are formed therein.

The dispersion plate 17 is provided at a substantially intermediate position in the thickness direction of the shower head 10, and is substantially parallel to the surface direction of the shower head 10. A gas introduction hole 15 (see FIG. 3) is formed at the center of the ceiling portion 11 of the shower head 10, and the gas introduction hole 15 leads to the upstream chamber 13. Further, a gas introduction pipe 16 is connected to the gas introduction hole 15, and the gas introduction pipe 16 is connected to a gas supply source (not shown). An upstream chamber 13 is formed between the ceiling portion 11 and the dispersion plate 17. A shower plate 12 is provided at the bottom of the shower head 10. A downstream chamber 14 is formed between the shower plate 12 and the dispersion plate 17.

A plurality of gas blowing holes 31 are formed in the shower plate 12. As shown in FIG. 2, each of the gas blowing holes 31 is formed in a slit shape extending in parallel with each other. The shower plate 12 is opposed to the processing space 20 via the upper heater 21. The upper heater 21 is composed of, for example, a plurality of sheathed heaters or lamp heaters, and the gas blown from the gas blowing holes 31 of the shower plate 12 passes through the plurality of sheathed heaters or the lamp heaters. The gap is blown to the substrate 5 housed in the processing space 20.

A plurality of through holes 32 (see FIG. 4) for connecting the upstream chamber 13 and the downstream chamber 14 are formed in the dispersion plate 17. The gas introduced into the upstream chamber 13 from the gas introduction hole 15 flows into the downstream chamber 14 through the through hole 32 of the dispersion plate 17, and the gas system flowing into the downstream chamber 14 flows from the gas blowing hole 31 of the shower plate 12 toward the shower electrode. The outside of the board is blown out.

Here, in the present embodiment, a structure in which the conductivity is gradually increased so that the pressure on the upstream side is high and the pressure on the downstream side is low is generated in the flow from the inlet to the outlet in the shower head 10.

Specifically, the through hole 32 and the gas blowing hole 31 are provided so that the gas blowing hole 31 is not provided (not overlapping) directly below the position of the through hole 32 of the dispersion plate 17 (the position in the surface direction of the dispersion plate 17). The position of the direction of the face is staggered. The center of the through hole 32 is located directly above the portion of the shower plate 12 where the gas blowing hole 31 is not formed.

Further, the total opening area of all the gas blowing holes 31 is formed to be larger than the total opening area of all the through holes 32. For example, the opening area of each of the through holes 32 may be smaller than the opening area of each of the gas blowing holes 31, and the number of the through holes 32 may be smaller than the number of the gas blowing holes 31. Alternatively, the opening area of each of the through holes 32 and the gas blowing holes 31 may be the same, and only the number of the through holes 32 may be made small.

With such a configuration, since the total area of the opening having the dispersion plate 17 and formed in the through hole 32 of the dispersion plate 17 is not large, the gas introduced into the upstream chamber 13 at a relatively high pressure does not immediately flow into the downstream chamber 14 Instead, it diffuses in the surface direction in the upstream chamber 13 and gradually fills the inside of the upstream chamber 13. The gas system filled in the upstream chamber 13 flows into the downstream chamber 14 through the through holes 32 of the dispersion plate 17.

Further, since the positions of the through holes 32 and the gas blowing holes 31 of the shower plate 12 are shifted, the gas flowing into the downstream chamber 14 from the through holes 32 of the dispersion plate 17 is not immediately blown out from the gas blowing holes 31. Instead, it spreads in the downstream direction in the surface of the downstream chamber 14 and is widely distributed in the downstream chamber 14.

Therefore, the gas introduced into the shower head 10 follows the inside of the shower head 10 The upstream side is advanced toward the downstream side, and its potential (speed and pressure) is gradually weakened so that the surface direction is evenly distributed, and the specific gas blowing hole 31 can be directed over the entire surface of the shower plate 12, and from all gases. The blowing hole 31 uniformly blows out the gas.

Further, a plurality of internal heaters 18 are provided in the shower head 10. Each of the internal heaters 18 is supported by the dispersion plate 17 and disposed in the upstream chamber 13, and both ends thereof penetrate the side wall of the shower head 10 and are connected to a power source (not shown).

Hereinafter, a treatment method using the heat treatment apparatus of the present embodiment will be described.

In the embodiment of the present invention, the substrate 5 to be processed is, for example, a substrate for a flat panel display or a solar cell. In particular, the heat treatment apparatus of the present embodiment can efficiently perform a large substrate having a length of one meter or more. Equal heating and cooling treatment.

The substrate 5 is carried into the processing space 20 from the carry-out port 25 by, for example, a transport robot arm. The substrate 5 is located between the upper heater 21 and the lower heater 22 in the processing space 20, and is supported by a support portion (not shown). The upper heater 21 faces the substrate 5, and the lower heater 22 faces the lower surface of the substrate 5, and each of them mainly heats the substrate 5 with radiant heat.

The inside of the sealed container 1 including the processing space 20 in which the substrate 5 is housed and held is decompressed. After depressurizing the inside of the processing space 20 to, for example, about 0.6 Pa, the upper heater 21 and the lower heater 22 are activated to start heating of the substrate 5.

The temperature in the substrate 5 or the processing space 20 is monitored by a temperature measuring means (not shown). When the temperature reaches a desired temperature, gas is introduced into the shower head 10, and the gas is blown out from the gas blowing hole 31. Gas system used here An inert gas such as nitrogen or the like with respect to the substrate 5.

The substrate 5 is heated by atmospheric pressure or a gas pressure slightly higher than atmospheric pressure by the gas replacement after the decompression. The gas introduced from the gas introduction hole 15 fills the upstream chamber 13 as described above, and at this time, the gas in the upstream chamber 13 is heated by the internal heater 18 provided in the upstream chamber 13. Further, the heated gas flows into the downstream chamber 14 through the through hole 32 of the dispersion plate 17, and is then blown out from the gas blowing hole 31 to the lower side of the shower head 10. This gas is blown onto the substrate 5 to heat the substrate 5.

The heated gas is blown with respect to the substrate 5, and the temperature of the heated substrate 5 is not lowered by the upper heater 21 and the lower heater 22, so that efficient and uniform heat treatment can be performed. Only by heating the upper heater 21 and the lower heater 22, the substrate 5 can be heated to a desired temperature in a relatively short period of time, but is particularly likely to be generated in the plane direction when the size of the substrate 5 is large. Uneven heating. However, in the present embodiment, in addition to the heating by the upper heater 21 and the lower heater 22, the heated head gas is blown onto the substrate 5 from the shower head 12 which is distributed in the direction of the surface of the substrate 5. Therefore, heat treatment can be uniformly performed while suppressing uneven heating in the surface direction of the substrate 5.

Further, as described above, when the gas enters the shower head 10, it is not immediately blown out, but is diffused in the surface direction to the extent that it is filled in the shower head 10. Therefore, the gas can be uniformly blown out without unevenness in the surface direction. Therefore, uniform heating which further suppresses heating unevenness in the surface direction of the substrate 5 can be achieved.

Further, as shown in FIG. 1, the covers 23 and 24 surrounding the processing space 20 are provided below the processing space 20, whereby the gas blown from the shower head 10 is filled in the processing space 20. Thereby, it is less affected by the position of the exhaust port 26 The heating gas is uniformly distributed in the direction of the surface of the substrate 5, which also contributes to the uniform heating of the substrate 5.

Further, when the heated gas is blown to the substrate 5, the heater 18 may be provided inside the shower head 10, and the gas heated outside the shower head 10 may be introduced into the shower head 10. However, by heating the gas in the shower head 10, it is possible to suppress the temperature drop of the gas when reaching the substrate 5, and to perform efficient heat treatment. Further, since the internal heater 18 is disposed closer to the upstream than the through hole 32 and the gas blowing hole 31, it is possible to heat the gas before dispersing the gas in a plurality of small holes, and to uniformize the temperature distribution in the gas surface direction. .

The substrate 5 is subjected to heat treatment at a temperature of, for example, 100 to 1000 ° C for several minutes to several tens of hours by blowing of the upper heater 21, the lower heater 22, and the gas.

Further, only one of the heater 21 and the lower heater 22 may be provided. However, it is preferable to provide both the upper heater 21 and the lower heater 22 from the viewpoint of heating the substrate 5 to a desired temperature in a short period of time and shortening the overall processing time.

Further, by providing the shower head 10 on the upper heater 21, the radiant heat of the upper heater 21 is not blocked by the shower head 10, and further, the gas blown from the shower head 10 is passed through the upper heater 21. The plurality of sheathed heaters or the lamp heaters are heated at that time, so that the temperature at which the substrate 5 is reached is not easily lowered.

After the heat treatment of the substrate 5, the upper heater 21 and the lower heater 22 are turned off, and the supply of the heating gas from the shower head 10 is stopped to bring the temperature of the substrate 5 Drop (back to normal temperature). At this time, in order to lower the temperature of the substrate 5 to a normal temperature as soon as possible, it is effective to blow the unheated gas from the shower head 10 to the substrate 5. In other words, the gas is introduced into the shower head 10 while the internal heater 18 is turned off, and is blown out from the gas blowing hole 31 to be blown onto the substrate 5.

At this time, in the same manner as in the case of the above-described heating, the gas is blown to the surface direction of the substrate 5 without any difference, whereby breakage such as cracking due to a temperature difference in the surface direction of the substrate 5 can be prevented.

According to the embodiment of the present invention described above, the heater 21 and the lower heater 22 rapidly raise the temperature of the substrate 5 to a desired temperature, and by using the gas supply of the shower head 10, the gas can be blown without any difference. It is attached to the entire surface of the substrate 5 to be heated or cooled. Thereby, a temperature difference is hard to occur in the surface of the substrate, and the processing quality can be improved and damage can be prevented.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited thereto, and various modifications can be made based on the technical idea of the present invention.

The gas to be blown onto the substrate is not limited to the above-described embodiments as long as it is an inert gas that does not react or deteriorate with respect to the substrate (including a film formed on the substrate). Moreover, the type of gas during heating and cooling of the substrate can also be changed.

5‧‧‧Substrate

10‧‧‧Sprinkler

12‧‧‧ shower plate

13‧‧‧Upstream room

14‧‧‧ downstream room

15‧‧‧ gas introduction hole

17‧‧‧Distribution board

18‧‧‧Internal heater

20‧‧‧Processing space

21‧‧‧Upper heater

22‧‧‧ Lower heater

26‧‧‧Exhaust port

31‧‧‧ gas blowing holes

32‧‧‧through holes

1 is a schematic view showing a configuration of a main part of a heat treatment apparatus according to an embodiment of the present invention; FIG. 2 is a perspective view of the shower head shown in FIG. 1 from a lower side; FIG. 3 is a cross-sectional view of the same shower head; Figure 4 is an enlarged view of the main part of the shower head shown in Figure 3.

1‧‧‧Contained container

5‧‧‧Substrate

10‧‧‧Sprinkler

11‧‧‧Surface Department

16‧‧‧ gas introduction tube

18‧‧‧Internal heater

20‧‧‧Processing space

21‧‧‧Upper heater

22‧‧‧ Lower heater

23‧‧‧Upper cover

24‧‧‧Under cover

25‧‧‧ moving out of the entrance

26‧‧‧Exhaust port

Claims (7)

A heat treatment apparatus comprising: a sealed container that can be sealed with respect to the atmosphere; a processing space that can accommodate a substrate in the sealed container; a heater that is disposed opposite to the processing space in the sealed container; and a spray a shower head having a gas introduction hole into which a gas which is inert to the substrate and which heats or cools the substrate is introduced, and the gas which is disposed opposite to the substrate and introduced into the inside through the gas introduction hole is directed toward the substrate a plurality of gas blowing holes are blown out, and the shower head is disposed in the sealed container; and an upstream chamber that connects the gas introduction hole side and a downstream chamber on the gas blowing hole side are disposed inside the shower head a dispersion plate; a plurality of through holes for connecting the upstream chamber and the downstream chamber; and a total area of all openings of the plurality of gas blowing holes being larger than a total area of all openings of the plurality of through holes Is large; in the interior of the aforementioned shower head into which the gas is introduced, the pressure of the upstream chamber is higher than that of the downstream chamber High power; blow-out hole from the gas space of the process of blowing the gas has been reduced, and to replace the inside of the gas space of the process. The heat treatment apparatus according to claim 1, wherein a position of a surface of the through hole in a surface direction of the dispersion plate is shifted from a position of the gas blowing hole. The heat treatment apparatus of claim 1 or 2, wherein an internal heater is disposed in the aforementioned shower head. The heat treatment apparatus according to claim 3, wherein the internal heater is disposed closer to the upstream than the through hole and the gas blowing hole. A heat treatment apparatus according to claim 1, wherein said heater has a pair of heaters opposed to each other across said processing space. A heat treatment method for depressurizing a processing space in which a substrate is housed; after the depressurization, heating the substrate by a heater disposed opposite to the processing space; and heating by the heater After the substrate or the processing space reaches a desired temperature, the gas that is inert to the substrate and heated is blown from the shower head disposed opposite the substrate to the substrate to heat the substrate; The upstream side and the downstream side of the inner portion of the shower head are separated into a plurality of spaces by the dispersion plate, and the gas system introduced into the shower head is diffused in the space of the plurality of spaces, and is gradually advanced toward the downstream side. The pressure is slowly falling. The heat treatment method according to claim 6, wherein the heating of the substrate is performed by blowing the heater and the gas, the heater is turned off, and the unheated gas is blown from the shower head to the substrate. The aforementioned substrate is cooled.