JP2004128428A - Device for replacing gas in foup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means in which gas replacement with an inert gas is executed by performing vacuum suction following after preventing the occurrence of a pressure difference by making a vacuum container communicate with the inside of an FOUP after putting the FOUP in the vacuum container, accordingly, an atmosphere in the FOUP is replaced by an inert gas with an inert gas consumption amount almost equal to a capacity of the vacuum container and with concentration almost equal to an inert gas supply source, and at the same time, handling of the FOUP whose gas is replaced can be automated. <P>SOLUTION: An opening/closing mechanism 10 of a sealing plug 17 of an FOUP 1 purge port is mounted inside the vacuum container 6. A flange opening/closing mechanism is provided to a front flange 8 and a rear flange 9 of the vacuum container 6. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gas replacement in a FOUP (Front Opening Un, fixed Pot), which is a container for 300 mm wafers used in semiconductor manufacturing, for replacing an atmosphere in a FOUP with an inert gas or dry air (hereinafter collectively referred to as an inert gas). It concerns the device.
[0002]
[Prior art]
In order to prevent surface oxidation of the wafer 5 in the FOUP 1, it is effective to fill an inert gas in the FOUP 1. To fill the FOUP 1 with an inert gas, one of the purge ports 4 (usually two places) of the FOUP 1 is connected to an inert gas supply source 31 to introduce the inert gas from the purge port 4 and to supply the other purge port. From step 4, the mixed gas of the atmosphere in the FOUP 1 and the inert gas is discharged. When the concentration of the inert gas reaches a certain level, the introduction of the inert gas is stopped, and the purge port 4 is sealed with the plug 17 of the purge port.
[0003]
Further, at present, gas replacement in the FOUP 1 is performed separately from the production line.
[0004]
[Problems to be solved by the invention]
In the conventional method, a large amount of inert gas must be kept flowing for a long time to obtain a high concentration of inert gas. It is efficient to directly evacuate the atmosphere in the FOUP and fill the inert gas with an inert gas. However, the FOUP is manufactured on the assumption that it is used under the atmospheric pressure. The structure is unbearable. Therefore, it is not possible to directly evacuate the FOUP. According to the present invention, the FOUP is placed in a vacuum container, the vacuum container and the FOUP are communicated with each other so that a pressure difference does not occur, and the atmosphere in the FOUP is reduced to approximately the volume of the vacuum container by evacuation and introduction of an inert gas. The objective is to replace the inert gas with a concentration that is approximately equal to the consumption of the inert gas and the source of the inert gas.
[0005]
It is a further object of the present invention to provide means for automating the handling of a FOUP for gas replacement by the above-mentioned apparatus.
[0006]
It is a further object of the present invention to provide means capable of automating the handling of a FOUP to be gas-replaced by the above-described apparatus, and a FOUP to be gas-replaced following loading and unloading of a wafer in the FOUP.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is that an opening / closing mechanism of a sealing plug of a FOUP purge port is mounted in a vacuum vessel.
[0008]
According to a second aspect of the present invention, a flange opening / closing mechanism is attached to the front flange, the rear flange, or both of the vacuum vessel so that the handling of the FOUP for gas replacement can be automated.
[0009]
According to a third aspect of the present invention, a FOUP door opening / closing mechanism is attached to the second aspect so that the gas inside the FOUP can be replaced after the wafer is taken in and out of the FOUP.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG. Embodiment 1 will be described with reference to FIGS. 2A and 2B. In FIG. 2 a), the vacuum vessel 6 is composed of a vacuum vessel main body 7 and a front flange 8 and a rear flange 9 that can be opened and closed. A FOUP placing table 12, a FOUP fixing mechanism 11, and a purge port opening / closing mechanism 10 are attached to the vacuum vessel body 7. Further, an evacuation valve 13 for evacuation, a gas introduction valve 14 for introducing an inert gas, and an atmosphere release valve 15 for releasing the atmospheric pressure are attached to the vacuum vessel body 7, and a vacuum evacuation system 30 and an inert gas supply are provided, respectively. Attached in connection with the source 31 and the atmosphere. Further, a pressure sensor 16 for detecting the pressure in the vacuum vessel 6 is attached.
[0011]
To perform the gas replacement in the FOUP 1, the front flange 8 is opened, and the FOUP 1 is placed in the vacuum vessel 6 at a position where the purge port 4 of the FOUP 1 and the opening / closing mechanism 10 of the sealing plug of the purge port can be fitted together. At 11 the FOUP 1 is fixed and the front flange 8 is closed. FIG. 2a) shows the situation. Next, as shown in FIG. 2B), the closing plug 17 of the purge port is opened by the opening / closing mechanism 10 of the closing plug of the purge port, the vacuum container 6 and the inside of the FOUP 1 are communicated, the exhaust valve 13 is opened, and the chamber is evacuated. The exhaust valve 13 is closed at the set pressure of the low pressure side pressure sensor 16a set to a low pressure, and the evacuation is stopped. Next, the gas introduction valve 14 is opened, an inert gas is introduced, the introduction of the inert gas is stopped at the set pressure of the atmospheric pressure side pressure sensor 16b set to a high pressure near the atmospheric pressure, and the sealing plug 17 of the purge port is closed. Close and cut off the communication between the vacuum vessel 6 and the inside of the FOUP 1. Returning to the state of FIG. 2 a), the atmosphere in the FOUPI is replaced by an inert gas having a volume approximately equal to that of the vacuum vessel 6 and a concentration approximately equal to that of the inert gas supply source 31.
[0012]
Embodiment 2 FIG. Embodiment 2 will be described with reference to FIG. A front flange opening / closing mechanism 18 including a mechanism for moving horizontally and a mechanism for moving vertically is added to the front flange 8. When the front flange 8 is opened, it first moves in a direction away from the vacuum vessel main body 7 in the horizontal direction, and then moves downward. When closing the front flange 8, the front flange 8 is raised and then moved in the direction in which the vacuum vessel main body 7 is in a horizontal direction. An opening and closing mechanism can be similarly added to the rear flange 9. With the front flange 8 or the rear flange 9 opened, it is possible to transfer the FOUP 1 between the automatic transfer equipment in the semiconductor factory (not shown) or the transfer robot of the FOUP stocker (not shown) in the semiconductor factory and the gas replacement device in the FOUP of the present invention. Become.
[0013]
Embodiment 3 FIG. Embodiment 3 will be described with reference to FIGS. A FOUP front / rear moving mechanism 25 for moving the FOUP 1 back and forth into the vacuum vessel 6 and a FOUP door opening / closing mechanism 27 on the rear flange 9 are added. The FOUP front-rear movement mechanism 25 is connected to a slide stage 23 on which the FOUP 1 is mounted by a connection plate 26, and the slide stage 23 moves back and forth on a guide rail 24. The FOUP door opening / closing mechanism 27 is provided with a latch key opening / closing mechanism 20 for releasing and locking the latch of the FOUP door 3, a registration pin 21, and a suction pad 22 for sucking and fixing the FOUP door 3. FIG. 4 shows the configuration. In order to open the FOUP door 3 of the FOUP 1 placed in the vacuum vessel 6, the slide stage 23 on which the FOUP 1 is mounted is moved forward by the FOUP front-rear movement mechanism 25 and is brought into close contact with the rear flange 9. Next, the FOUP door 3 is suction-fixed by the suction pad 22, and the latch is released by the latch key opening / closing mechanism 20. Next, the rear flange 9 is opened. The FOUP 1 can take in and out a wafer by a wafer transfer robot (not shown). FIG. 5 shows a state in which a wafer can be taken in and out by the wafer transfer robot. After the completion of loading and unloading of the wafer, the back flange 9 is closed, the FOUP door 3 is closed, the front flange 8 is closed, the FOUP 1 is returned to a gas-replaceable position, and the FOUP 1 is fixed by the FOUP fixing mechanism 11. FIG. 4 shows a state in which the FOUP 1 is returned to a gas-replaceable position. Next, the FOUP purge port sealing plug opening / closing mechanism 10 opens the FOUP purge port sealing plug 17 to perform evacuation and gas replacement with an inert gas. If the FOUP purge port sealing plug 17 is sealed, the inside of the FOUP 1 will be filled. Replaced with an inert gas. If the front flange 8 is opened, the FOUP 1 can be transferred between an automatic transfer device or a transfer robot of a FOUP stocker (not shown) in the semiconductor factory and the gas replacement device in the FOUP of the present invention.
[0014]
It is apparent that the present invention is not limited to the above embodiments, and each embodiment can be appropriately modified within the scope of the technical idea of the present invention. Further, the number, position, shape, and the like of the constituent mechanisms and members are not limited to the above-described embodiment, but can be set to numbers, positions, shapes, and the like suitable for carrying out the present invention.
[0015]
【The invention's effect】
As described above, according to the present invention, the atmosphere in the FOUP used in the semiconductor production line can be replaced with an inert gas having a volume substantially equal to that of the vacuum vessel and a concentration substantially equal to the inert gas supply source. By using a vacuum pumping system having a high pumping speed, the gas in the vacuum vessel can be pumped in a short time, so that gas replacement can be performed in a short time.
[0016]
According to the present invention, handling of a FOUP to be replaced with an inert gas is facilitated, and a means for incorporating the FOUP into an automatic transfer line can be provided.
[0017]
Further, according to the present invention, the handling of the FOUP to be replaced with the inert gas and the FOUP to be replaced with the gas after the loading / unloading of the wafer in the FOUP becomes easy, and a means for incorporating the FOUP into the automatic transfer line can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a conventional gas replacement method.
FIGS. 2 (a) and 2 (b) illustrate a first embodiment of the present invention: a) a state in which a FOUP is placed in a vacuum vessel and a state in which gas replacement is completed; It is a schematic sectional drawing which shows a state.
FIG. 3 is a schematic sectional view showing a state in which a FOUP according to a second embodiment of the present invention can be handled.
FIG. 4 is a schematic cross-sectional view showing a state where a FOUP according to a third embodiment of the present invention is placed in a vacuum vessel and a state where gas replacement is completed.
FIG. 5 is a schematic sectional view showing a state in which a FOUP door according to a third embodiment of the present invention is opened.
[Explanation of symbols]
1 FOUP
2 FOUP box 3 FOUP door 4 Purge port 5 Wafer 6 Vacuum container 7 Vacuum container main body 8 Front flange 9 Rear flange 10 Purge port sealing plug opening / closing mechanism 11 FOUP fixing mechanism 12 FOUP holder 13 Exhaust valve 14 Gas introduction valve 15 Atmosphere Opening valve 16 Pressure sensor 16a Low pressure side pressure sensor 16b Atmospheric pressure side pressure sensor 17 Purge port sealing plug 18 Front flange opening / closing mechanism 19 Rear flange opening / closing mechanism 20 Latch key opening / closing mechanism 21 Registration pin 22 Suction pad 23 Slide stage 24 Guide rail 25 FOUP back-and-forth moving mechanism 26 Connecting plate 27 FOUP door opening and closing mechanism 30 Vacuum exhaust system 31 Inert gas supply source

Claims (3)

When replacing the atmosphere in the FOUP 1 with an inert gas, the FOUP 1 is put into the vacuum vessel 6, and the sealing plug 17 of the purge port of the FOUP 1 is opened and closed to communicate the vacuum vessel 6 and the FOUP 1, thereby evacuating and inerting. A gas replacement device in a FOUP, wherein an atmosphere in the FOUP 1 is replaced with an inert gas by introducing a gas. 2. A gas replacement device in a FOUP, wherein an opening and closing mechanism is added to the front flange 8 and / or the rear flange 9 of the vacuum vessel 6 according to claim 1. 3. A gas replacement device in a FOUP, wherein a FOUP door opening / closing mechanism 27 is added to claim 2.

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