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Researchers Submit Patent Application, "Inactive Gas Introducing Facility and Inactive Gas Introducing Method", for Approval

February 4, 2014



By a News Reporter-Staff News Editor at Life Science Weekly -- From Washington, D.C., NewsRx journalists report that a patent application by the inventors Shin, Takeshi (Gamo-gun, JP); Takahara, Masahiro (Gamo-gun, JP); Ueda, Toshihito (Gamo-gun, JP), filed on January 3, 2013, was made available online on January 23, 2014 (see also Daifuku Co., Ltd.).

The patent's assignee is Daifuku Co., Ltd.

News editors obtained the following quote from the background information supplied by the inventors: "The inactive gas introducing facility described above is used for e.g. introducing an amount of inactive gas into a container accommodating a substrate (such as a semiconductor wafer) for the purpose of restricting unwanted adhesion and accumulation of particles on the substrate thereby to avoid deterioration of the substrate from its proper state due to oxygen and/or humidity.

"More particularly, in association with the introduction of inactive gas through the gas feed opening of the container accommodating the substrate, gas present inside the container will be discharged to the inside of a storage space through a gas discharge opening of the container and the interior of the container will be filled with the introduced inactive gas eventually. Therefore, unwanted adhesion of particles on the substrate and deterioration of the substrate from its proper state due to oxygen and/or humidity are restricted.

"Japanese Unexamined Patent Application Publication No. 2001-338971 (Patent Document 1) discloses an example of such inactive gas introducing facility. With this inactive gas introducing facility, a plurality of storing sections as storage sections are disposed in juxtaposition along the vertical and right/left directions within a box-like storage and each storing section includes a gas feed pipe for feeding nitrogen gas as inactive gas.

"Though not detailed in Patent Document 1 above, the interior of the box-like storage corresponds to 'a storage space partitioned from the outside' and into this box-like storage, the nitrogen gas is discharged from a container.

"In the inactive gas introducing facility, there is generally provided an inspection door for allowing access by a worker to/from the inside of the storage space in order to carry out various inspection operations.

"In case such inspection door is provided, in order to restrict discharge of inactive gas to the inside of the storage space through the gas discharge opening of the container stored in the storage section, it is conceivable to arrange such that feeding of inactive gas is stopped in response to opening of the inspection door.

"However, with the simple arrangement of stopping feeding of inactive gas in response to opening of the inspection door, inspection operations with feeding of inactive gas, such as inspection operation of feeding state of inactive gas to the gas feed opening of the container stored in the storing section, inspection operation of the discharge state of the inactive gas through the gas discharge opening of the container are not possible."

As a supplement to the background information on this patent application, NewsRx correspondents also obtained the inventors' summary information for this patent application: "In view of the above-described background, there is a need for realizing an inactive gas introducing facility that allows not only inspection operations with stopping of inactive gas feeding, but also inspection operations with continued feeding of inactive gas.

"An inactive gas introducing facility according to the present invention comprises:

"a storage shelf disposed in a storage space partitioned from the outside and having storage sections each storing a container for accommodating a substrate;

"an introducing device for introducing inactive gas to the inside of the container stored in the storage section through a gas feed opening of the container with discharging gas present inside the container to the inside of the storage space through a gas discharge opening of the container;

"a controller for controlling operation of the introducing device;

"an inspection-door opening/closing detecting device for detecting an opened/closed state of an inspection door allowing access of a worker to/from the inside of the storage space; and

"a manual operation type stop nullification commanding device for issuing a stop nullification command to the controller;

"wherein in a normal stop mode which is executed when the stop nullification command is not issued by the stop nullification commanding device, the controller controls the operation of the introducing device to stop feeding of inactive gas to the container if the inspection-door opening/closing detecting device detects an opened state of the inspection door; and

"in a stop nullification mode which is executed when the stop nullification command is issued by the stop nullification commanding device, the controller controls the operation of the introducing device to continue feeding of inactive gas to the container even if the inspection-door opening/closing detecting device detects the opened state of the inspection door.

"With the above-described arrangement, in carrying out e.g. inspection of the feeding state of inactive gas to the gas feed opening of the container stored in the storage section, inspection of the discharging state of inactive gas through the gas discharge opening of the container, etc. as an inspection with feeding of inactive gas, as the stop nullification commanding device issues a stop nullification command to the controller, the state of feeding inactive gas to the container can be contained even if the inspection door is opened. As a result, the inspection operation can be carried out with the feeding of inactive gas to the container being continued.

"Further, in case feeding of inactive gas to the container is not needed at the time of inspection operation, as the stop nullification commanding device does not issue a stop nullification command to the controller, if the inspection-door opening/closing detecting device detects the opened state of the inspection door, the feeding of inactive gas to the container is stopped. As a result, the inspection operation can be carried out with the feeding of inactive gas to the container being stopped.

"In short, with the above-described arrangement, there can be provided an inactive gas introducing facility that allows not only an inspection operation with feeding of inactive gas being stopped, but also an inspection operation with feeding of inactive gas being continued.

"The technical features of the inactive gas introducing facility relating to the present invention is applicable also to an inactive gas introducing method; hence, the invention can claim such method in its scope for protection. With this inactive gas introducing method too, the same advantageous effect achieved by the above-described inactive gas introducing facility can be achieved.

"That is, according to the present invention, an inactive gas introducing method utilizing an inactive gas introducing facility including

"a storage shelf disposed in a storage space partitioned from the outside and having storage sections each storing a container for accommodating a substrate;

"an introducing device for introducing inactive gas to the inside of the container stored in the storage section through a gas feed opening of the container with discharging gas present inside the container to the inside of the storage space through a gas discharge opening of the container;

"a controller for controlling operation of the introducing device;

"an inspection-door opening/closing detecting device for detecting an opened/closed state of an inspection door allowing access of a worker to the inside of the storage space; and

"a manual operation type stop nullification commanding device for issuing a stop nullification command to the controller;

"the method comprising the following step that is effected by the controller:

"a feeding state controlling step wherein in a normal stop mode which is executed when the stop nullification command is not issued by the stop nullification commanding device, the operation of the introducing device is controlled to stop feeding of inactive gas to the container if the inspection-door opening/closing detecting device detects an opened state of the inspection door; and

"wherein in a stop nullification mode which is executed when the stop nullification command is issued by the stop nullification commanding device, the operation of the introducing device is controlled to continue feeding of inactive gas to the container even if the inspection-door opening/closing detecting device detects the opened state of the inspection door.

"Next, preferred embodiments of the present invention will be explained.

"According to a preferred embodiment of the inactive gas introducing facility relating to the present invention,

"there is provided an oxygen concentration detecting sensor for detecting an oxygen concentration inside the storage space; and

"if the oxygen concentration detecting sensor detects an oxygen concentration below a set value while feeding of inactive gas to the container is continued in the stop nullification mode, the controller controls the operation of the introducing device to stop feeding of the inactive gas to the container.

"With the above-described arrangement, in the stop nullification mode, if the oxygen concentration inside the storage space falls below the set value due to discharging of inactive gas into the storage space via the gas discharge opening of the container, feeding of inactive gas to the container will be stopped, so that safety for the worker can be ensured.

"That is, the storage space is not formed to be completely sealed in order to discharge gas discharged from the container to the outside, but the storage space is appropriately open to be capable of communicating air with the outside space. Further, when an inspection operation is to be carried out, the inspection door will be kept under the opened state. Therefore, even if inactive gas is discharged into the storage space through the gas discharge opening of the container, there is not much possibility of the oxygen concentration inside the storage space falling too sharply to be below the set value. However, if the oxygen concentration inside the storage space should fall below the set value, the safety for the worker can be ensured with stopping of feeding of inactive gas to the container.

"According to a further preferred embodiment of the inactive gas introducing facility relating to the present invention, in the stop nullification mode, when feeding of inactive gas to the container is to be continued after detection of the opened state of the inspection door by the inspection-door opening/closing detecting device, the controller activates a notifying device for notifying continuation of feeding of inactive gas to the worker.

"With the above-described arrangement, when the worker is to carry out an inspection operation inside the storage space, the worker can accurately understand that feeding of inactive gas to the container is being continued. Therefore, the worker can carry out the inspection operation appropriately with the recognition of the feeding of inactive gas to the container being continued.

"Incidentally, as the notifying device, it is possible to employ an arrangement that continuation of feeding of inactive gas is notified to a portable terminal such as a mobile phone carried by the worker or an arrangement that continuation of feeding of inactive gas is notified through a speaker provided adjacent the inspection door, etc.

"According to a further preferred embodiment of the inactive gas introducing facility relating to the present invention, if the inspection-door opening/closing detecting device does not detect the opened state of the inspection door even after lapse of a set period after switchover to the stop nullification mode in response to the stop nullification command from the stop nullification commanding device, the controller releases the stop nullification mode and switches it over to the normal stop mode.

"With the above-described arrangement, for instance, even when the worker issues the stop nullification command to the controller via the stop nullification commanding device in order to carry out an inspection operation with feeding operation of inactive gas to the container being continued and then the worker decides to cancel this inspection operation for some reason, the stop nullification mode will be cancelled and switched over to the normal stop mode automatically. Therefore, unnecessary continuation of the stop nullification mode can be avoided.

"That is, if the stop nullification mode is continued, when the worker erroneously believing the current mode being the normal stop mode opens the inspection door and enters the storage space, the state of feeding inactive gas to the container will be continued, in spite of the worker's understanding to the contrary. The above arrangement can avoid occurrence of such inconvenience.

"According to a further preferred embodiment of the inactive gas introducing facility relating to the present invention, the stop nullification commanding device includes an operational member selectively operable between an operation canceling position and a nullification commanding position and urged to return to the operation canceling position; and the stop nullification command is issued to the controller when the operational member is operated to the nullification commanding position.

"When the operational member is not urged to return to the operation canceling position and the stop nullification mode will be cancelled and automatically switched over to the normal stop mode, the worker who saw the operational member maintained at the nullification commanding position may erroneously believe that the stop nullification mode being currently executed. With the above-described arrangement, such misunderstanding by the worker of the mode being currently the stop nullification mode can be avoided.

"According to a preferred embodiment of the inactive gas introducing method relating to the present invention,

"the inactive gas introducing facility further includes an oxygen concentration detecting sensor for detecting an oxygen concentration inside the storage space; and

"at the feeding state controlling step, if the oxygen concentration detecting sensor detects an oxygen concentration below a set value while feeding of inactive gas to the container is continued in the stop nullification mode, the operation of the introducing device is controlled to stop feeding of the inactive gas to the container.

"According to a still preferred embodiment of the inactive gas introducing method relating to the present invention, at the feeding state controlling step, when feeding of inactive gas to the container is to be continued after detection of the opened state of the inspection door by the inspection-door opening/closing detecting device, a notifying device is activated for notifying the continuation of feeding of inactive gas to the worker.

"According to a still preferred embodiment of the inactive gas introducing method relating to the present invention,

"at the feeding state controlling step, if the inspection-door opening/closing detecting device does not detect the opened state of the inspection door even after lapse of a set period after switchover to the stop nullification mode in response to the stop nullification command from the stop nullification commanding device, the stop nullification mode is released and then switched over to the normal stop mode.

"According to a still preferred embodiment of the inactive gas introducing method relating to the present invention, the stop nullification commanding device includes an operational member selectively operable between an operation canceling position and a nullification commanding position and urged to return to the operation canceling position; and the stop nullification command is issued to the controller when the operational member is operated to the nullification commanding position.

BRIEF DESCRIPTION OF THE DRAWINGS

"FIG. 1 is a front view in vertical section showing an article storage facility,

"FIG. 2 is a cutaway side view showing the facility,

"FIG. 3 is a perspective view showing a storage section,

"FIG. 4 is an explanatory view illustrating an introducing condition of nitrogen gas, and

"FIG. 5 is a flowchart showing control operations."

For additional information on this patent application, see: Shin, Takeshi; Takahara, Masahiro; Ueda, Toshihito. Inactive Gas Introducing Facility and Inactive Gas Introducing Method. Filed January 3, 2013 and posted January 23, 2014. Patent URL: http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.html&r=5920&p=119&f=G&l=50&d=PG01&S1=20140116.PD.&OS=PD/20140116&RS=PD/20140116

Keywords for this news article include: Nitrogen, Chalcogens, Daifuku Co. Ltd..

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Source: Life Science Weekly


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