JP6250947B2 - Heat treatment equipment - Google Patents

Description

  The present invention relates to a heat treatment apparatus for performing a heat treatment on a workpiece enclosed in a chamber.

  In the heat treatment apparatus, various kinds of gases and vapors are introduced into the chamber when heat-treating the workpiece enclosed in the chamber. Since the gas introduced into the chamber includes flammable gas, it is necessary to prevent leakage of the flammable gas.

  Moreover, it is preferable that the heat treatment apparatus is configured not only to prevent the leakage of the flammable gas during normal times, but also to prevent the expansion of damage in the event of an emergency such as an earthquake or fire.

  For example, when a chamber for performing a heat treatment on a semiconductor substrate or a glass substrate is damaged, the housing is also damaged by a sudden pressure change inside the housing surrounding the chamber, and as a result, combustible gas leaks from the housing. In addition, there is a possibility that damage is expanded by oxygen outside the apparatus touching a heat source in the housing.

  Therefore, by using a flexible member such as a soft shell for at least a part of the casing that hermetically surrounds the chamber, even if the chamber is damaged and the internal pressure of the casing suddenly changes, the flexible member In response to this, a technique for a heat treatment apparatus that contracts or expands to prevent damage to the housing has been proposed (see, for example, Patent Document 1). This conventional technique can prevent damage to the casing due to sudden changes in internal pressure without configuring the casing with a pressure-resistant member, so that the effect of expanding damage caused by chamber damage can be realized at low cost. .

JP 2009-231522 A

  However, in the conventional technique described in Patent Document 1, when the flexible member is installed inside the heat treatment apparatus, it is relatively easy to apply the technique to a newly manufactured heat treatment apparatus. In order to apply the above technique to the heat treatment apparatus later, many parts of the existing heat treatment apparatus need to be disassembled once, and the problem that workability is poor remains.

  An object of the present invention is to provide a heat treatment apparatus that can prevent damage to a casing against pressure fluctuation caused by breakage of a chamber, and can be realized with low cost and good workability even in an existing heat treatment apparatus.

The heat treatment apparatus according to the present invention performs a heat treatment on a workpiece enclosed in a chamber. The heat treatment apparatus includes an apparatus main body and an external unit that is externally attached to the apparatus main body. The apparatus main body includes a heating unit that is disposed around the chamber and heats the workpiece in the chamber, and a housing that forms an enclosure space that surrounds the heating unit and the chamber . The housing is provided with an opening. The external portion includes a soft shell that forms a spare space that communicates with the surrounding space via the opening . The soft shell is provided so that an outer peripheral edge thereof surrounds the opening on the outside of the housing. Also, soft shell, that have a flexibility to change the volume depending on the internal pressure of the airtight space defined by the surrounding space and pre space.

  In this configuration, even if the chamber is damaged and the internal pressure of the airtight space suddenly changes, the soft shell contracts or expands according to the internal pressure of the airtight space, thereby reducing the load on the housing and preventing the housing from being damaged. Is done. For this reason, the airtightness around the heating unit and the chamber is maintained even after the chamber is broken. Therefore, since the heating unit does not come into contact with oxygen outside the apparatus, combustion of the combustible gas is prevented even when the combustible gas leaked from the chamber comes into contact with the heating unit.

  In addition, since the external part including the soft shell is configured to be externally attached to the apparatus main body, the soft shell can be easily attached to the existing heat treatment apparatus, the chamber is damaged, and the internal pressure is suddenly changed. It is possible to prevent the case from being damaged.

  In the above-described configuration, it is preferable that the soft shell is sealed with a caulking material at a gap between the soft shell and the apparatus body.

  In this configuration, incombustible gas such as nitrogen is supplied to the airtight space in order to reduce the oxygen concentration in the airtight space so that combustion of the combustible gas due to heater heating can be prevented even if the combustible gas leaks. The airtightness between the soft shell and the apparatus main body can be airtightly treated with a caulking material without using a solid sealing material such as an O-ring. For this reason, it is easy to perform the work of attaching the soft shell to prevent the casing from being damaged to the existing heat treatment apparatus.

  Moreover, it is preferable that the volume of the spare space is equal to or greater than the volume of the chamber.

  According to this configuration, even if it is assumed that the inside of the chamber is 0 atm and the airtight space composed of the enclosed space and the spare space is 1 atm, the soft shell contracts when the chamber is damaged, so that the chamber is damaged. The subsequent airtight space is maintained at 1 atm. Therefore, even when the chamber is damaged, the load on the housing can be minimized.

  Moreover, it is preferable that an external attachment part further includes the attachment housing | casing which incorporates a soft shell, and the space between an attachment housing | casing and a soft shell communicates with external space.

  According to this configuration, since the soft shell is built in the attached housing, the soft shell is prevented from being damaged due to an object being caught on the soft shell from the outside. In addition, since the space between the attached housing and the soft shell communicates with the external space of the heat treatment apparatus, the load when the soft shell contracts and expands can be reduced.

  Furthermore, it is preferable to further include a blower that circulates the gas in the enclosed space and the gas in the spare space.

  According to this configuration, it is possible to prevent unevenness in pressure and temperature in the airtight space including the enclosed space and the spare space, and unevenness in mixing when plural kinds of gases are mixed.

  According to the present invention, it is possible to realize prevention of expansion of damage at the time of occurrence of an emergency with low cost and good workability even in an existing heat treatment apparatus.

It is a figure which shows the schematic structure of the heat processing apparatus which concerns on embodiment of this invention.

  A heat treatment apparatus 10 according to an embodiment of the present invention will be described with reference to FIG. The heat treatment apparatus 10 is configured to perform heat treatment on a semiconductor substrate or a glass substrate in a reduced pressure state, for example. Examples of the heat treatment include chemical vapor deposition, diffusion, and annealing.

  The heat treatment apparatus 10 includes an apparatus main body 20 and an external part 30.

  The apparatus main body 20 includes a housing 21, a chamber 22, a heater 23, a blower 24, a pressure gauge 25, a thermometer 26, an oxygen concentration meter 27, an inert gas supply unit 28, an instrument chamber cover 29, a gas supply unit 51, and a gas. A discharge unit 52 and a control unit 53 are provided. The control unit 53 comprehensively controls each component device.

  The chamber 22 defines a processing chamber in which heat treatment is performed. As an example, the chamber 22 is made of quartz glass. The heater 23 is disposed around the chamber 22 and is configured to heat the workpiece in the chamber 22. The heater 23 constitutes a heating unit.

Gas is supplied into the chamber 22 by a gas supply unit 51. The gas supplied into the chamber 22 may contain a combustible gas. Examples of the gas supplied into the chamber 22 include silane (SiH ₄ ), argon (Ar), nitrogen (N ₂ ), and the like. Any gas selected from these gases is supplied into the chamber 22 as necessary.

  The gas discharge part 52 has an exhaust pipe provided with, for example, an air valve and a manual valve, and is configured to exhaust from the chamber 22. Further, the gas discharge unit 52 includes a decompression pump for decompressing the inside of the chamber 22. For example, a vacuum pump is mentioned as a decompression pump.

  The casing 21 defines a surrounding space 41 that surrounds the chamber 22 and the heater 23.

  The pressure gauge 25 measures the pressure in the enclosed space 41. The thermometer 26 measures the temperature of the enclosed space 41. The oxygen concentration meter 27 measures the oxygen concentration in the enclosed space 41.

  The inert gas supply unit 28 includes a supply pipe provided with a flow rate adjustment valve, a pressure gauge, a flow meter, a manual valve, and the like, and is configured to supply nitrogen to the enclosed space 41. The supply of nitrogen to the surrounding space 41 is performed based on the detection result of the oximeter 27. The inert gas supply unit 28 is controlled to supply nitrogen to the enclosed space 41 when the oxygen concentration in the enclosed space 41 exceeds a predetermined concentration (for example, 5%). By increasing the nitrogen concentration in the enclosed space 41, the oxygen concentration can be reduced, thereby preventing combustion due to heating of the heater.

  The instrument chamber cover 29 is disposed adjacent to the casing 21 and constitutes an instrument chamber 45 in which the pressure gauge 25, the thermometer 26, and the oxygen concentration meter 27 are disposed.

  The external part 30 is configured to be externally attached to the apparatus main body 20. For this reason, the external attachment part 30 can be retrofitted while minimizing the modification to the apparatus main body 20. As an example, the externally attached portion 30 is externally attached so as to be adjacent to both the casing 21 and the instrument room cover 29.

  The external part 30 has a soft shell 31 and an attached housing 32. Examples of the configuration of the soft shell 31 include a configuration in which a glass cloth is covered with an aluminum foil and adhered with a resin or the like, such as an aluminum glass cloth, and a commercially available one can be used. However, the soft shell 31 only needs to have a heat resistance function, a function of maintaining airtightness, and a function of absorbing a pressure difference between inside and outside, and is not limited to the above-described materials.

  As an example, the soft shell 31 is configured such that the edge 311 is applied to the outer surface of the apparatus main body 20 and the application plate 61 and the edge are placed with the application plate 61 applied between the apparatus body 20 and the edge 311. It is attached to the apparatus main body 20 by a fastener 62 such as a screw that penetrates the portion 311 from the abutting plate 61 side. Further, the gap between the edge 311 of the soft shell 31 and the apparatus main body 20 is sealed with the caulking material 63.

  Examples of the caulking material include silicon-based (organopolysiloxane), modified silicon-based (polyether having a silyl group at the terminal), polyurethane-based resin, and the like.

  The soft shell 31 is built in the attached housing 32. The attached housing 32 has a communication hole 33. The communication hole 33 allows the space 42 between the attached housing 32 and the soft shell 31 to communicate with the external space 43 of the heat treatment apparatus 10.

  Since the soft shell 31 is built in the attached housing 32, damage to the soft shell 31 due to an object being caught on the soft shell 31 from the outside is prevented. Further, since the space 42 between the attached housing 32 and the soft shell 31 communicates with the external space 43 through the communication hole 33, the load when the soft shell 31 contracts and expands is reduced.

  An opening 211 is provided on the wall surface of the casing 21 to which the external part 30 is externally attached. The soft shell 31 is attached to the wall surface of the apparatus main body 20 so as to cover the opening 211. The spare space 44 formed by the soft shell 31 and the enclosed space 41 formed by the housing 21 communicate with each other through the opening 211.

  The casing 21 and the soft shell 31 are formed so that the space formed by the surrounding space 41 and the spare space 44 has airtightness. The soft shell 31 has flexibility to change the volume according to the internal pressure of the airtight space constituted by the surrounding space 41 and the spare space 44.

  The air blower 24 has a blower pipe provided with a radiator 241 and a blower 242 and is disposed in the instrument chamber 45. The blower 24 circulates the gas in the surrounding space 41 and the gas in the spare space 44 by sucking the gas in the surrounding space 41 and discharging it to the spare space 44. As a result, it is possible to prevent air pressure and temperature unevenness in the airtight space constituted by the enclosed space 41 and the spare space 44, and uneven mixing when plural kinds of gases are mixed.

  With the above-described configuration, in the heat treatment apparatus 10, when the chamber 22 is damaged due to an earthquake or the like, the decompressed space in the chamber 22 and the airtight space communicate with each other, but the soft shell 31 is bent inward and airtight. By reducing the volume of the space, a decrease in the internal pressure of the airtight space is suppressed or prevented.

  As described above, the soft shell 31 absorbs the decrease in the internal pressure of the airtight space, so that the load on the casing 21 can be reduced and the casing 21 can be prevented from being damaged even after the chamber 22 is damaged. In addition, the area around the heater 23 can be kept airtight. For this reason, even when the chamber 22 is damaged, the casing 21 is prevented from being damaged, and the combustible gas can be prevented from leaking outside the heat treatment apparatus 10. Moreover, inflow of oxygen from outside the airtight space can be prevented, and combustion of combustible gas leaked from the chamber 22 due to heating of the heater 23 is prevented.

  Furthermore, by using the soft shell 31, the cost can be reduced as compared with the case where the surroundings of the chamber 22 and the heater 23 are all surrounded by a pressure-resistant member.

  Further, since the external portion 30 including the soft shell 31 is configured to be externally attached to the apparatus main body 20, the soft shell 31 can be easily attached to an existing heat treatment apparatus, and the chamber 22 is damaged. Thus, the housing 21 can be prevented from being damaged due to a sudden change in internal pressure.

  Therefore, it is possible to realize the prevention of the expansion of damage at the time of occurrence of an emergency situation with low cost and good workability even in the existing heat treatment apparatus.

  In the heat treatment apparatus 10, nitrogen is supplied to the airtight space in order to reduce the oxygen concentration in the airtight space so that the combustion of the combustible gas by the heated heater 23 can be prevented even when the combustible gas leaks. The airtightness between the soft shell 31 and the apparatus main body 20 can be airtightly treated with a caulking material without using a solid sealing material such as an O-ring. For this reason, it is not necessary to prepare the material suitable for each heat processing apparatus as a material for an airtight process.

  The maximum volume of the soft shell 31, that is, the maximum volume of the spare space 44 is preferably equal to or greater than the volume of the chamber 22. According to this configuration, assuming that the inside of the chamber 22 is 0 atm and the airtight space including the enclosed space 41 and the spare space 44 is 1 atm, the soft shell 31 contracts when the chamber 22 is damaged, The airtight space after the chamber 22 is broken is maintained at 1 atm. Therefore, even when the chamber 22 is damaged, the load on the housing 21 can be minimized.

  The above description of the embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 10 ... Heat processing apparatus 20 ... Apparatus main body 21 ... Housing | casing 22 ... Chamber 23 ... Heater (heating part)
24 ... Blower part 30 ... External part 31 ... Soft shell 32 ... Attached case 33 ... Communication hole 41 ... Enclosed space 44 ... Preliminary space

Claims (7)

A heat treatment apparatus for performing heat treatment on a workpiece enclosed in a chamber,
An apparatus main body, and an external part externally attached to the apparatus main body,
The apparatus main body is
A heating unit for heating the workpiece in the chamber;
A housing that forms a surrounding space that surrounds the heating unit and the chamber,
The housing is provided with an opening,
The external part is
A soft shell that forms a preliminary space communicating with the surrounding space through the opening , the outer peripheral edge of the soft shell including a soft shell provided to surround the opening on the outside of the housing;
Said soft shell, that have a flexibility to change the volume depending on the internal pressure of the airtight space defined by the enclosing space and the pre space, the heat treatment apparatus. The heat treatment apparatus according to claim 1, wherein a volume of the preliminary space is equal to or greater than a volume of the chamber. The heat treatment apparatus according to claim 1, wherein the outer peripheral edge of the soft shell is attached to an outer surface of the housing. The heat treatment apparatus according to claim 3, wherein a gap between the outer peripheral edge portion of the soft shell and the outer surface of the housing is sealed with a caulking material. The external part further includes an attachment housing containing the soft shell,
The heat treatment apparatus according to any one of claims 1 to 4 , wherein a space between the auxiliary housing and the soft shell communicates with an external space. The heat processing apparatus in any one of Claims 1-5 further provided with the ventilation part which circulates the gas in the said surrounding space, and the gas in the said reserve space. The feed air portion includes a radiator for cooling the gas to circulate, heat treatment apparatus according to claim 6.

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