JP2010182766A - Apparatus and method of heat treatment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of cooling an object after heat treatment in a short time without damaging the object when heat-treating the object in an atmosphere gas environment. <P>SOLUTION: This invention is actualized as the heat treatment apparatus for heat-treating the object in the atmosphere gas environment. The heat treatment apparatus includes a conveyance container for housing the object and an atmosphere gas, a heating device for heating the conveyance container, and a cooling device for cooling the conveyance container. In the heat treatment apparatus, when conveying the conveyance container from the heating device to the cooling device, the object housed in the conveyance container is not brought into contact with a jig for conveyance. Thus, a situation that the object at a high temperature immediately after the heat treatment is executed is brought into contact with the jig for conveyance at a normal temperature and the object is damaged by a heat shock is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an apparatus and method for heat-treating an object in an atmospheric gas environment.

  When processing a semiconductor wafer, various heat treatments such as an oxidation process, a diffusion process, a reflow process, an annealing process, and a sintering process are performed. Conventionally, in these heat treatments, after the semiconductor wafer is accommodated in the accommodation chamber, an atmospheric gas is introduced into the accommodation chamber, and the semiconductor wafer is heated and maintained at a high temperature. When the heat treatment is completed, the high-temperature semiconductor wafer is cooled and taken out from the storage chamber, and is transferred to the next step.

  A technique for shortening the time required for cooling the heat-treated semiconductor wafer has been developed. For example, in Patent Document 1, a heating chamber for heating a semiconductor wafer and a cooling chamber for cooling the semiconductor wafer are disposed adjacent to each other, and the semiconductor wafer after the heat treatment is transferred from the heating chamber to the cooling chamber, Cool in the cooling chamber. With such a configuration, the time required for cooling the heat-treated semiconductor wafer can be shortened.

JP 2000-243719 A

  When the heated semiconductor wafer is cooled, it is preferable that the semiconductor wafer be transferred to a cooling device provided separately from the heating device and cooled. When a semiconductor wafer is transferred from the heating device to the cooling device, it is necessary to hold the semiconductor wafer with a transfer jig. However, if a high-temperature semiconductor wafer immediately after the heat treatment is brought into contact with a transfer jig at normal temperature, a local heat shock may act on the semiconductor wafer, which may cause damage to the semiconductor wafer.

  In order to prevent the semiconductor wafer from being damaged by the heat shock as described above, a method of cooling the semiconductor wafer to a certain temperature inside the heating device before unloading from the heating device can be considered. However, immediately after the heat treatment of the semiconductor wafer is completed, not only the semiconductor wafer but also the heating device itself is at a high temperature. Therefore, when the semiconductor wafer is cooled before being unloaded from the heating device, the heating device itself needs to be cooled in order to prevent heat transfer from the high-temperature heating device to the semiconductor wafer. Since the heat capacity of the heating device is extremely large compared to the heat capacity of the semiconductor wafer, a long time is required for cooling.

  There is a need for a technique that can cool a semiconductor wafer that has been subjected to heat treatment in a short time without causing damage to the semiconductor wafer.

  The present invention solves the above problems. The present invention provides a technique capable of cooling an object after heat treatment in a short time without causing damage to the object when the object including a semiconductor wafer is heat-treated in an atmospheric gas environment. To do.

  The present invention is embodied as a heat treatment apparatus for heat-treating an object in an atmospheric gas environment. The heat treatment apparatus includes a transport container that stores an object and atmospheric gas, a heating device that heats the transport container, and a cooling device that cools the transport container.

  In said heat processing apparatus, a target object and atmospheric gas are accommodated in a conveyance container, and a conveyance container is heated with a heating apparatus. By heating the transfer container, the object accommodated therein is also heated, and the object is heat-treated in an atmospheric gas environment. Thereafter, the transport container is transported from the heating device to the cooling device, and the transport container is cooled by the cooling device. By cooling the transfer container, the object accommodated therein is also cooled. Since the transfer container and the object are cooled using a cooling device different from the heating device, it is not necessary to cool the heating device itself having a large heat capacity, and the object can be cooled in a short time.

  In the above heat treatment apparatus, when the transfer container is transferred from the heating apparatus to the cooling apparatus, the object accommodated in the transfer container does not come into contact with the transfer jig. Therefore, it is possible to prevent a situation in which a high-temperature target object immediately after being subjected to heat treatment comes into contact with a normal temperature transfer jig and the target object is damaged by a heat shock.

  As for said heat processing apparatus, it is preferable that the conveyance container is formed with the high heat conductive material.

  In the above heat treatment apparatus, since the transport container is formed of a high heat conductive material, the heating efficiency of the transport container by the heating device and the cooling efficiency of the transport container by the cooling device can be increased. The time required for heating and cooling can be further shortened.

  In said heat processing apparatus, it is preferable that a cooling device cools a conveyance container by flowing cooling gas along the outer surface of a conveyance container.

  The transport container immediately after being heated by the heating device is at a high temperature, and if it is naturally cooled at room temperature, it takes a long time to be sufficiently cooled. According to the above heat treatment apparatus, the time required for cooling can be further shortened by forcibly cooling the transfer container with the cooling gas.

  In said heat processing apparatus, it is preferable that a cooling apparatus is provided with the surface by which the black process was performed facing the outer surface of a conveyance container.

  According to said heat processing apparatus, the heat absorption from a conveyance container to a cooling device can be accelerated | stimulated by the radiant heat transfer from the high temperature conveyance container to the surface by which the black process was carried out. The time required for cooling can be further shortened.

  The heat treatment apparatus further includes a second cooling device that cools the object, and after cooling the transport container with the cooling device, the object taken out from the transport container is preferably cooled with the second cooling device.

  According to said heat processing apparatus, after cooling a conveyance container and a target object to a certain temperature with the cooling device which cools a conveyance container, a target object can be directly cooled with a 2nd cooling device. Compared with the case where the transport container containing the object is cooled by the cooling device, the object can be cooled more quickly by directly cooling the object by the second cooling device. In this case, after the transfer container is cooled by the cooling device, the object is also cooled to a certain temperature, so that the heat shock due to the contact with the transfer jig does not occur so much. The time required for cooling can be further shortened without damaging the object.

  The present invention can also be embodied as a method. The method of the present invention is a heat treatment method in which an object is heat treated in an ambient gas environment. The method includes a step of accommodating an object and atmospheric gas in a transport container, a step of heating the transport container with a heating device, and a step of cooling the transport container with a cooling device.

  In the heat treatment method described above, it is preferable that the transport container is formed of a high heat conductive material.

  In the above heat treatment method, it is preferable to cool the transport container by flowing a cooling gas along the outer surface of the transport container in the step of cooling the transport container with the cooling device.

  In the heat treatment method, in the step of cooling the transport container with the cooling device, it is preferable to cool the transport container also by radiant heat transfer to the black-treated surface facing the outer surface of the transport container.

  The heat treatment method preferably further includes a step of cooling the object taken out from the transfer container by the second cooling device after the step of cooling the transfer container by the cooling device.

  According to the heat treatment apparatus and the heat treatment method of the present invention, the object after the heat treatment can be cooled in a short time without causing damage to the object when the object is heat-treated in an atmospheric gas environment.

FIG. 1 is a diagram schematically illustrating a configuration of a heat treatment apparatus 100 according to the first embodiment. FIG. 2 is a diagram schematically illustrating the configuration of the heating device 104 according to the first embodiment. FIG. 3 is a diagram schematically illustrating the configuration of the first cooling device 106 according to the first embodiment. FIG. 4 is a diagram schematically illustrating the configuration of the second cooling device 108 according to the first embodiment. FIG. 5 is a diagram schematically illustrating a configuration of a first cooling device 500 that can be used in place of the first cooling device 106 of the first embodiment.

The main features of the embodiments described below are first organized.
(Feature 1) The object is a semiconductor wafer.

  The heat treatment apparatus 100 of the present embodiment shown in FIG. 1 performs heat treatment on the semiconductor wafer W in the oxidation process of the semiconductor wafer W. The heat treatment apparatus 100 mainly includes a transfer chamber 102, a heating device 104, a first cooling device 106, a second cooling device 108, a chamber transfer arm 110, and a wafer transfer arm 112.

  The transfer chamber 102 is a substantially rectangular parallelepiped container formed of a high heat conductive material (for example, SiC, Si, C, AlN, etc.). A susceptor 114 on which the semiconductor wafer W is placed is provided inside the transfer chamber 102. On the side surface of the transfer chamber 102, an entrance / exit 116 for taking in / out the semiconductor wafer W and an opening / closing plate 118 for closing the entrance / exit 116 are provided. Although not shown, the transfer chamber 102 includes a port and an on-off valve for sealing atmospheric gas inside.

  After the semiconductor wafer W is accommodated in the transfer chamber 102, the atmosphere gas is sealed inside the transfer chamber 102. In this embodiment, oxygen gas and hydrogen gas in amounts necessary for oxidizing the semiconductor wafer W are sealed as the atmospheric gas.

  The transfer chamber 102 containing the semiconductor wafer W and the atmospheric gas therein is transferred with the side surfaces held by the chamber transfer arm 110. The transfer chamber 102 is transferred from the work table 120 to the heating device 104.

  As shown in FIG. 2, the heating device 104 includes a lower heating container 202 and an upper heating container 204. The position of the lower heating container 202 is fixed, and the upper heating container 204 is movable in the vertical direction with respect to the lower heating container 202. With the upper heating container 204 moved upward, the transfer chamber 102 is placed on the lower heating container 202 by the chamber transfer arm 110. Thereafter, by moving the upper heating container 204 downward, the heating device 104 is sealed while the transfer chamber 102 is accommodated therein.

  In a state where the transfer chamber 102 is accommodated in the heating device 104, the lower surface of the transfer chamber 102 is in contact with the inner surface of the lower heating container 202 with almost no gap, and the side surface and the upper surface of the transfer chamber 102 are the upper heating container 204. It touches the inner surface with almost no gap.

  The lower heating container 202 includes a soaking plate 206 on the inner surface. The soaking plate 206 is made of a highly heat conductive material (for example, SiC, Si, C, AlN, etc.), and the temperature distribution in the surface of the soaking plate 206 is made uniform. The lower heating container 202 further includes a heater 208 provided outside the soaking plate 206 so as to cover the soaking plate 206, and a heat insulating material 210 provided outside the heater 208 so as to cover the heater 208. Yes.

  The upper heating container 204 includes a soaking plate 212 on the inner surface. The soaking plate 212 is made of a highly heat conductive material (for example, SiC, Si, C, AlN, etc.), and the temperature distribution in the surface of the soaking plate 212 is made uniform. The upper heating container 204 further includes a heater 214 provided outside the soaking plate 212 so as to cover the soaking plate 212, and a heat insulating material 216 provided outside the heater 214 so as to cover the heater 214. .

  The heating device 104 accommodates the inside of the transfer chamber 102 and seals it, and then starts heating by the heaters 208 and 214. The heat from the heaters 208 and 214 uniformly heats the outer surface of the transfer chamber 102 via the soaking plates 206 and 212. As a result, the temperature of the transfer chamber 102 rises.

  When the transfer chamber 102 is heated to a high temperature, the semiconductor wafer W is heated by radiant heat transfer from the inner surface of the transfer chamber 102. Further, the semiconductor wafer W is also heated by the convection heat transfer of the atmospheric gas accommodated inside the transfer chamber 102. As a result, an oxidation reaction occurs on the surface of the semiconductor wafer W. The heating by the heaters 214 and 216 is continued until the time required for the oxidation reaction of the semiconductor wafer W elapses.

  When the heating process in the heating device 104 is completed, the upper heating container 204 is moved upward, the side surface of the transfer chamber 102 is gripped by the chamber transfer arm 110, and the transfer chamber 102 is unloaded from the heating device 104. At this time, both the transfer chamber 102 and the semiconductor wafer W accommodated therein are at a high temperature. However, in the present embodiment, the room temperature chamber transfer arm 110 is in contact with the transfer chamber 102 but is not in contact with the semiconductor wafer W. Therefore, the high temperature semiconductor wafer W does not come into contact with the transfer jig at normal temperature, and the semiconductor wafer W is not damaged by the heat shock. The transfer chamber 102 carried out of the heating device 104 is carried into the first cooling device 106 by the chamber transfer arm 110.

  As shown in FIG. 3, the first cooling device 106 includes a lower cooling container 302 and an upper cooling container 304. The position of the lower cooling container 302 is fixed, and the upper cooling container 304 is movable in the vertical direction with respect to the lower cooling container 302. The lower cooling container 302 is provided with chamber support pins 306 for supporting the transfer chamber 102. With the upper cooling container 304 moved upward, the transfer chamber 102 is placed on the chamber support pins 306 of the lower cooling container 302. Thereafter, by moving the upper cooling container 304 downward, the cooling device 106 is hermetically sealed with the transfer chamber 102 accommodated therein.

  A lower cooling gas supply path 308 is formed in the lower cooling container 302. On the inner surface of the lower cooling vessel 302, a plurality of inlets 310 for introducing the cooling gas into the interior from the lower cooling gas supply path 308 are provided. In addition, a lower cooling gas discharge path 312 is formed in the lower cooling container 302. A plurality of discharge ports 314 for discharging the cooling gas from the inside to the lower cooling gas discharge path 312 are provided on the inner surface of the lower cooling container 302.

  An upper cooling gas supply path 316 is formed in the upper cooling container 304. A plurality of inlets 318 are provided on the inner surface of the upper cooling container 304 to introduce the cooling gas into the inside from the upper cooling gas supply path 316.

  On the inner surface of the lower cooling vessel 302 and the inner surface of the upper cooling vessel 304, black processing is applied to the portions where the inlets 310 and 318 and the outlet 314 are not provided.

  The first cooling device 106 accommodates and seals the transfer chamber 102 therein, and then cools the transfer chamber 102 with a cooling gas. When the cooling gas is supplied to the lower cooling gas supply path 308 and the upper cooling gas supply path 316, the cooling gas is introduced into the first cooling device 106. As the cooling gas flows along the outer surface of the transfer chamber 102, the outer surface of the transfer chamber 102 is cooled. Since the transfer chamber 102 is mounted on the chamber support pin 306, the cooling gas also flows below the transfer chamber 102 and the lower surface of the transfer chamber 102 is also cooled. The cooling gas that has cooled the transfer chamber 102 is discharged from the lower cooling gas discharge path 312 to the outside.

  Further, the transfer chamber 102 immediately after being transferred to the first cooling device 106 is at a high temperature. The transfer chamber 102 is also cooled by the radiant heat transfer from the high temperature transfer chamber 102 to the inner surface of the lower cooling vessel 302 and the inner surface of the upper cooling vessel 304 that have been blackened. Cooling with the cooling gas is continued until the transfer chamber 102 and the semiconductor wafer W are cooled to a certain temperature.

  When the cooling process in the first cooling device 106 is completed, the upper cooling container 304 is moved upward, the side surface of the transfer chamber 102 is gripped by the chamber transfer arm 110, and the transfer chamber 102 is unloaded from the first cooling device 106. The transfer chamber 102 is placed on the work table 120 in FIG.

  Thereafter, the opening / closing plate 118 of the transfer chamber 102 is opened, and the semiconductor wafer W is taken out of the transfer chamber 102 by the wafer transfer arm 112. At this time, since the semiconductor wafer W has been cooled to a certain temperature, it does not receive much heat shock when contacting the wafer transfer arm 112 at room temperature. The semiconductor wafer W is transferred to the second cooling device 108 by the wafer transfer arm 112.

  As shown in FIG. 4, the second cooling device 108 includes a lower cooling container 402 and an upper cooling container 404. The position of the lower cooling container 402 is fixed, and the upper cooling container 404 is movable in the vertical direction with respect to the lower cooling container 402. The lower cooling container 402 is provided with wafer support pins 406 for supporting the semiconductor wafer W. With the upper cooling container 404 moved upward, the semiconductor wafer W is placed on the wafer support pins 406 of the lower cooling container 402. Thereafter, by moving the upper cooling container 404 downward, the second cooling device 108 is sealed with the semiconductor wafer W accommodated therein.

  A lower cooling gas supply path 408 is formed in the lower cooling container 402. A plurality of inlets 410 through which cooling gas is introduced from the lower cooling gas supply path 408 is provided on the inner surface of the lower cooling container 402. Further, a lower cooling gas discharge path 412 is formed in the lower cooling container 402. A plurality of discharge ports 414 for discharging the cooling gas from the inside to the lower cooling gas discharge path 412 are provided on the inner surface of the lower cooling container 402.

  An upper cooling gas supply path 416 is formed in the upper cooling container 404. A plurality of inlets 418 are provided on the inner surface of the upper cooling container 404 to introduce the cooling gas into the inside from the upper cooling gas supply path 416.

  The second cooling device 108 accommodates and seals the semiconductor wafer W therein, and then cools the semiconductor wafer W with a cooling gas. When the cooling gas is supplied to the lower cooling gas supply path 408 and the upper cooling gas supply path 416, the cooling gas is introduced into the second cooling device 108. When the cooling gas flows along the outer surface of the semiconductor wafer W, the semiconductor wafer W is cooled. Since the semiconductor wafer W is placed on the wafer support pins 406, the cooling gas also flows below the semiconductor wafer W, and the semiconductor wafer W is cooled from the upper and lower surfaces. The cooling gas that has cooled the semiconductor wafer W is discharged from the lower cooling gas discharge path 412. When the semiconductor wafer W is cooled to room temperature, the second cooling device 108 ends the cooling with the cooling gas.

  When the cooling process in the second cooling device 108 is completed, the upper cooling container 404 is moved upward, the semiconductor wafer W is gripped by the wafer transfer arm 112, and the semiconductor wafer W is unloaded from the second cooling device 108. The semiconductor wafer W is transferred toward the next process.

  In the above embodiment, the case where the heat treatment apparatus 100 is used for the heat treatment in the oxidation process of the semiconductor wafer W has been described. However, other than this, for example, the diffusion process, reflow process, annealing process, sintering process of the semiconductor wafer W It can also be used for heat treatment. In each of these steps, the type of atmospheric gas used when heating the semiconductor wafer W is different. However, the time required for heating or cooling the semiconductor wafer W can be shortened by using the heat treatment apparatus 100 described above.

  In the above embodiment, the first cooling device 106 that cools the transfer chamber 102 is configured to cool the transfer chamber 102 by flowing a cooling gas along the outer surface of the transfer chamber 102. The cooling device 106 may be replaced with another configuration.

  For example, instead of the first cooling device 106 shown in FIG. 3, the first cooling device 500 shown in FIG. 5 may be used. The first cooling device 500 in FIG. 5 includes a lower cooling container 502 and an upper cooling container 504. The position of the lower cooling container 502 is fixed, and the upper cooling container 504 is movable in the vertical direction with respect to the lower cooling container 502. When the transfer chamber 102 is placed on the lower cooling container 502 with the upper cooling container 504 moved upward, and the upper cooling container 504 is moved downward, the transfer chamber 102 is accommodated inside. The cooling device 500 is sealed.

  In a state where the transfer chamber 102 is accommodated in the first cooling device 500, the lower surface of the transfer chamber 102 is in contact with the inner surface of the lower cooling container 502 without any gap, and the side surface and upper surface of the transfer chamber 102 are the upper cooling container 504. It touches the inner surface of the without gap.

  A plurality of refrigerant circulation paths 506 are formed in the lower cooling container 502. A plurality of refrigerant circulation paths 508 are formed in the upper cooling container 504. Low-temperature refrigerant flows through the refrigerant circulation paths 506 and 508. As the refrigerant, for example, cooling water, cooling gas, endothermic gel, or the like can be used. Further, a soaking plate 510 is provided on the inner surface of the lower cooling vessel 502, and a soaking plate 512 is provided on the inner surface of the upper cooling vessel 504.

  The first cooling device 500 accommodates and seals the transfer chamber 102 therein, and then cools the transfer chamber 102 by circulating a refrigerant. When the refrigerant is circulated through the refrigerant circulation paths 506 and 508, the lower cooling container 502 and the upper cooling container 504 are cooled to a low temperature and absorb heat from the transfer chamber 102. Heat from the high-temperature transfer chamber 102 is uniformly absorbed by the lower cooling container 502 and the upper cooling container 504 by the heat equalizing plates 510 and 512.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

DESCRIPTION OF SYMBOLS 100 Heat processing apparatus 102 Transfer chamber 104 Heating apparatus 106 1st cooling apparatus 108 2nd cooling apparatus 110 Chamber transfer arm 112 Wafer transfer arm 114 Susceptor 116 Entrance / exit 118 Opening / closing plate 120 Work table 202 Lower heating container 204 Upper heating container 206 Soaking plate 208 Heater 210 Heat insulating material 212 Heat equalizing plate 214 Heater 216 Heat insulating material 302 Lower cooling container 304 Upper cooling container 306 Chamber support pin 308 Lower cooling gas supply path 310 Inlet 312 Lower cooling gas discharge path 314 Outlet 316 Upper cooling Gas supply path 318 Inlet 402 Lower cooling container 404 Upper cooling container 406 Wafer support pin 408 Lower cooling gas supply path 410 Inlet 412 Lower cooling gas outlet 414 Outlet 416 Upper cooling gas supply path 418 Inlet 500 Cooling Below device 502 Cooling vessel 504 above the cooling vessel 506 refrigerant circulation channel 508 the coolant circulation path 510 soaking plate 512 equalizing plate

Claims (10)

A heat treatment apparatus for heat-treating an object in an atmospheric gas environment,
A transport container for containing an object and atmospheric gas;
A heating device for heating the transport container;
A heat treatment apparatus provided with a cooling device for cooling the transfer container.   The heat treatment apparatus according to claim 1, wherein the transfer container is made of a high heat conductive material.   The heat treatment apparatus according to claim 1 or 2, wherein the cooling device cools the transport container by flowing a cooling gas along the outer surface of the transport container.   The heat treatment apparatus according to claim 3, wherein the cooling device includes a black-treated surface facing the outer surface of the transport container. A second cooling device for cooling the object;
The heat treatment apparatus according to any one of claims 1 to 4, wherein the object taken out from the transfer container is cooled by the second cooling apparatus after the transfer container is cooled by the cooling apparatus. A heat treatment method for heat treating an object in an atmospheric gas environment,
Storing the object and atmospheric gas in a transport container;
Heating the transfer container with a heating device;
The heat processing method provided with the process of cooling a conveyance container with a cooling device.   The heat treatment method according to claim 6, wherein the transfer container is formed of a high heat conductive material.   The heat treatment method according to claim 6 or 7, wherein in the step of cooling the transport container with the cooling device, the transport container is cooled by flowing a cooling gas along the outer surface of the transport container.   The heat treatment method according to claim 8, wherein in the step of cooling the transport container with the cooling device, the transport container is also cooled by radiant heat transfer to the black-treated surface facing the outer surface of the transport container.   The heat treatment method according to any one of claims 6 to 9, further comprising, after the step of cooling the transport container with the cooling device, a step of cooling the object taken out from the transport container with the second cooling device.

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