JP3893635B2 - Gas supply and exhaust system for portable sealed containers - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a portable container used for transporting semiconductor wafers in a clean room, and more particularly to a gas supply / exhaust system that replaces the interior of the portable container with an inert gas atmosphere.
[0002]
[Prior art]
The semiconductor is manufactured in a clean room where the internal atmosphere is cleaned, and this semiconductor is also used in a clean environment equivalent to or better than that in the semiconductor processing equipment for transportation between processes in the clean room. Attempts have also been made to store wafer cassettes containing wafers in stages in a portable sealed container.
In addition, as semiconductor manufacturing progresses to the utmost limit, when the film thickness is thin and the conductors become ultrafine wires, the ultrathin oxide film due to natural oxidation of the semiconductor wafer begins to be regarded as a problem, and the gas inside the portable sealed container An inert gas (for example, nitrogen gas) is supplied by a replacement device to release oxygen causing natural oxide film growth of the semiconductor wafer out of the portable sealed container, and the atmosphere inside the container is replaced with an inert gas. is doing.
[0003]
As described above, the inventor of the present application proposes a gas supply / exhaust system for replacing the internal atmosphere of the portable sealed container with an inert gas, which will be described below.
In FIG. 3, the gas supply / exhaust system of the portable sealed container includes a gas replacement device 3 disposed in the clean room 1 and a gas exhaust pipe 4, and an inert gas (for example, on the gas replacement device 3) , Nitrogen gas) is placed on the portable sealed container 2 (hereinafter simply referred to as the sealed container 2). In this sealed container 2, a wafer cassette 7 for storing a semiconductor wafer W is placed on the lid 2 </ b> A and stored in an airtight manner.
Further, the gas displacement device 3 is provided with an elevation device 6 having an elevation table 5 inside, and the elevation table 5 is fitted into the upper opening 3A of the gas displacement device 3 to make the gas displacement device 3 airtight. I have to. The gas replacement device 3 includes an air supply pipe 8 that communicates an inert gas supply device (not shown) and the upper opening 3A, and an exhaust pipe that exhausts the inert gas supplied from the inert gas supply device. 4 are connected to each other. The gas exhaust pipe 4 includes an exhaust pipe 9 that opens into the gas replacement device 3, and a main exhaust pipe 4 A that extends to the outside of the clean room 1 continuously to the exhaust pipe 9. The main exhaust pipe 4A is disposed below the floor board 15 (grating) with holes in the clean room 1 so as not to hinder the operation of a semiconductor manufacturing apparatus or the like (not shown) disposed in the clean room 1 or a transport device. In addition, the exhaust gas from the semiconductor device or the like as well as the gas replacement device 3 is connected so as to be exhausted collectively. 10 is an air supply valve arranged in the air supply pipe 8, 11 is an exhaust valve arranged in the exhaust pipe 9, and 12 is an exhaust gas of each device drawn from the main exhaust pipe 4 </ b> A and released to the outside of the clean room. A suction fan 13 is a filter for removing dust and dirt present in the exhaust gas sucked by the suction fan 12.
[0004]
Then, in order to replace the inside of the sealed container 2 with an inert gas, the sealed container 2 covers the opening 3 </ b> A of the gas replacement device 3 and the gas replacement device 3 and the lifting platform 5 of the lifting device 6 are hermetically sealed. Then, the lid 2 </ b> A of the sealed container 2 is opened by coupling with the lifting platform 5. Then, the elevator 5 is lowered together with the lid 2A and the wafer cassette 7 to bring the inside of the sealed container 2 into communication with the gas replacement device 3, and then the air supply valve 10 and the exhaust valve 11 are opened and the suction fan 12 is opened. Is activated.
As a result, the inert gas is supplied from the inert gas supply device into the gas replacement device 3 and the sealed container 2, and oxygen gas or the like causing the natural oxide film growth of the semiconductor wafer W is exhausted together with the inert gas. After being sucked by the suction fan 12 and passing through the exhaust pipe 6 and the main exhaust pipe 4A, when passing through the filter 13, the air in the clean room 1 is also sucked from the floor board 15 with holes and released to the outside of the clean room 1. .
After that, when the predetermined time has elapsed and the purity of the inert gas in the gas replacement device 3 and the sealed container 2 is increased and replaced, the air supply valve 10 and the exhaust valve 11 are closed and the gas replacement device 3 is returned to. After the supply of the inert gas and the exhaust of the exhaust gas from the gas replacement device 3 are stopped, the lifting platform 5 of the lifting device 6 is lifted together with the lid 2A and the wafer cassette 7, and the wafer is hermetically sealed in the sealed container 2. The cassette 7 is stored.
[0005]
By the way, in the gas supply / exhaust system of the portable sealed container proposed by the present inventor in FIG. 3, the relationship between the semiconductor manufacturing apparatus arranged in the clean room and the securing of the travel route of the transfer device traveling in the clean room, etc. Therefore, there is no guarantee that the gas replacement device will be installed in the vicinity of the main exhaust pipe of the gas exhaust pipe, and if it is placed away from the main exhaust pipe, the exhaust pipe becomes longer and the longer exhaust pipe It is assumed that the exhaust resistance of the exhaust gas passing through the gas increases and exhaust cannot be performed satisfactorily. As a result, there arises a problem that the replacement performance of the gas replacement device that replaces the internal atmosphere of the sealed container with an inert gas is deteriorated.
[0006]
[Problems to be solved by the invention]
In order to solve this problem, the length of the exhaust pipe can be shortened by discharging the exhaust gas exhausted from the gas replacement device directly into the clean room without passing through the main exhaust pipe. The deterioration of the replacement performance of the gas replacement device due to the increase in exhaust resistance is eliminated. Further, the gas replacement device can be freely arranged in the clean room without noticing the installation position of the main exhaust pipe.
[0007]
However, when the exhaust gas from the gas replacement device is released into the clean room, the concentration of the exhaust gas in the clean room increases, resulting in an oxygen-deficient state. As a result, workers in the clean room are more likely to develop oxygen deficiency symptoms, and work in anxiety that they may fall into oxygen deficiency symptoms anytime and at any time, even without oxygen deficiency symptoms. Will do. In addition, the exhaust gas from the gas replacement device is discharged into the clean room, which causes a problem that it is not preferable in terms of hygiene.
[0008]
The present invention has been made to solve this problem, and converts the inert gas exhausted from the gas replacement device into a mixed gas that does not affect the operator and discharges it into the clean room. Provided is a gas supply / exhaust system of a portable sealed container that can achieve freedom of arrangement in a room and safety and health of an operator working in a clean room.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, in the gas supply / exhaust system for a portable sealed container according to the present invention, in claim 1, a portable sealed container that houses and seals a semiconductor wafer, and the inside of the portable sealed container is inert. Gas supply / exhaust of a portable sealed container comprising: a gas replacement device that replaces with gas; and a gas exhaust pipe that discharges exhaust gas containing the inert gas exhausted from the gas replacement device to the outside of the gas replacement device In the system, the exhaust gas exhausted from the gas replacement device is mixed with oxygen gas in the gas exhaust pipe, and the concentration of the mixed gas after mixing is set as a predetermined concentration region that does not affect the human body. A gas exhaust device that discharges the gas is connected. As a result, oxygen gas is mixed with the exhaust gas of the gas replacement device, and the concentration of the mixed gas after mixing is set to a predetermined concentration that does not affect the worker working in the clean room and released into the clean room. Can do.
[0010]
According to a second aspect of the present invention, there is provided the gas mixing chamber according to the first aspect, wherein the gas exhaust device mixes the exhaust gas exhausted from the gas replacement device through the gas exhaust pipe and the oxygen gas supplied from the outside. Gas concentration detection means for detecting the concentration of an inert gas or acidity gas of the mixed gas mixed in the gas mixing chamber, and a flow rate control means for changing the flow rate of the oxygen gas supplied into the gas mixing chamber And the concentration of the inert gas or oxygen gas in the mixed gas mixed in the gas mixing chamber based on the detection signal from the gas concentration detecting means is within a gas concentration setting region that does not affect the human body. And a control device for controlling the flow rate control means, and a cleaning chamber for cleaning and discharging the mixed gas with a filter.
Thus, based on the detection signal from the gas concentration detection means, the control device controls the flow rate control means so that the flow rate of the oxygen gas supplied to the gas mixing chamber becomes the flow rate of the exhaust gas exhausted from the gas replacement device. By changing it accordingly, it is surely controlled so that it is within the gas concentration setting region of the inert gas or oxygen gas of the mixed gas in the gas mixing chamber so as not to affect the worker working in the clean room. , Can be released into the clean room.
[0011]
According to a third aspect of the present invention, in addition to the second aspect of the present invention, the control device is connected to a concentration setting device capable of changing the gas concentration setting region.
Thereby, the gas concentration setting area | region of the inert gas or oxygen gas in the mixed gas of a gas mixing chamber can be set according to the environment in a clean room.
[0012]
According to a fourth aspect of the present invention, the gas replacement device and the gas exhaust device are integrally formed with the first or second aspect of the present invention. As a result, the gas supply / exhaust system becomes compact and can be transported easily.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a gas supply / exhaust system for a portable sealed container according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram showing a gas supply / exhaust system of a portable sealed container according to an embodiment of the present invention. FIG. 2 shows a gas replacement device constituting the gas supply / exhaust system of a portable sealed container according to an embodiment of the present invention. It is the longitudinal cross-sectional view which integrated the gas exhaust apparatus. 1 and 2, the same reference numerals as those in FIG. 3, which is the system proposed by the inventor of the present application, indicate the same members, and the description thereof will be omitted.
[0014]
In FIG. 1, a gas supply / exhaust system for a portable sealed container according to an embodiment of the present invention has a gas exhaust device 16 connected to the gas replacement device 3 shown in FIG. Thus, exhaust gas [mixed gas of inert gas (for example, nitrogen gas) and oxygen gas (air)] exhausted from the gas replacement device 3 can be exhausted into the clean room 1. This gas exhaust device 16 includes a gas mixing chamber 17, a flow rate control valve 18 serving as a flow rate control means for changing the flow rate of oxygen gas supplied into the gas mixing chamber 17, and gas replacement supplied into the gas mixing chamber 17. Based on the gas concentration sensor 19 which is a gas concentration detecting means for detecting the concentration of the mixed gas of exhaust gas and oxygen gas from the apparatus 3 and the output of the gas concentration sensor 19, the degree of opening of the flow rate control valve 18 is controlled. The control device 10 and a clean chamber 21 that cleans the mixed gas from the mixing chamber 17 and discharges it into the clean room 1 are mainly configured.
[0015]
The gas mixing chamber 17 communicates with the cleaning chamber 21 through the throttle tube 23. The clean chamber 21 is open in the clean room 1 on the side facing the side wall 21a where the throttle tube 23 is opened, and the filter 13 is inserted from the side of the opening to partition the fluid radiation space A between the side wall 21a. is doing. Further, the throttle tube 23 communicating the gas mixing chamber 17 and the clean chamber 21 has a smaller diameter than the chambers 17 and 23. That is, as will be described later, the mixed gas of the exhaust gas exhausted from the gas replacement device 3 into the gas mixing chamber 17 and the oxygen gas supplied from an oxygen gas reservoir (not shown) is throttled from the gas mixing chamber 17. The diameter of the throttle tube 23 is made smaller than each of the chambers 17 and 21 so as to flow out radially through the throttle tube 23 into the fluid radiation space A in the clean chamber 21.
[0016]
An exhaust pipe 9 connected to the gas replacement device 3 is opened on the side wall 17a facing the side wall where the throttle tube 23 of the gas mixing chamber 17 is opened. A suction device 25 (for example, a pump, a fan, or the like) is disposed that sucks exhaust gas exhausted from the exhaust gas and supplies the exhaust gas into the gas mixing chamber 17. Then, oxygen gas stored in an oxygen gas storage device (not shown) is supplied into the gas mixing chamber 17 from a direction orthogonal to the flow direction a of the exhaust gas supplied from the exhaust pipe 9 into the gas mixing chamber 17. The oxygen gas supply pipe 22 opens, for example, in the upper wall 17b of the gas mixing chamber 17.
[0017]
The oxygen gas supply pipe 22 has a suction device 30 (for example, a pump, a fan, etc.) for sucking oxygen gas from the oxygen gas storage device in order from the oxygen gas storage device side toward the gas mixing chamber 17. ) And a flow control valve 18 are arranged. The flow control valve 18 is connected to the control device 20 together with the suction devices 25 and 30 disposed in the exhaust pipe 9 and the oxygen gas supply pipe 22, and operates based on various commands of the control device 20. .
[0018]
The gas concentration detection means 19 is disposed in a throttle tube 23 that communicates the gas mixing chamber 17 and the clean chamber 21, and oxygen gas out of the mixed gas composed of exhaust gas and oxygen gas mixed in the gas mixing chamber 17. Gas concentration detection sensor (hereinafter referred to as oxygen gas concentration detection sensor 19) for detecting the content rate of oxygen (oxygen gas concentration), and the oxygen gas concentration corresponding to the oxygen gas concentration of the mixed gas passing through the throttle tube 23 The detection signal b is sent to the control device 20. Here, the oxygen gas concentration detection sensor 19 uses a characteristic of oxygen gas known as a paramagnetic gas that generates a small number of magnetic moments, for example, a magnetic wind method or a pressure detection type magnetic oxygen meter. It is done.
[0019]
When the control device 20 receives the oxygen gas concentration detection signal b from the oxygen gas concentration detection sensor 19, the oxygen gas concentration that does not affect the human body, which is preset in the inside or input by the concentration setter 16. The area data c (for example, an area in which the upper limit value of the oxygen concentration area data is set to 30% and the lower limit value is set to 18%) is compared with the oxygen gas concentration detection signal b, and the flow control valve 18 is opened. A valve opening degree command d (voltage) for determining the valve degree is sent to the flow control valve 18 and an operation command e is sent to the suction devices 25 and 30.
[0020]
The gas supply / exhaust system according to the embodiment of the present invention is configured as described above. Next, the operation of the gas supply / exhaust system will be described. For convenience of explanation, the air supply valve 10 and the flow rate control valve 18 in the air supply pipe 8 are in a closed state, the suction devices 25 and 30 are not in operation, and the elevator 5 is replaced with gas. It is assumed that the gas replacement device 3 is hermetically sealed by being fitted in the upper opening 3 </ b> A of the device 3.
[0021]
First, in order to replace the inside of the sealed container 2 with an inert gas, the sealed container 2 is covered with the gas replacement device 3 and the lifting platform 5 of the lifting device 6 in a state of covering the opening 3A of the gas replacement device 3. After mounting, the lifting platform 5 is raised and joined to the lid 2A of the sealed container 2 through the opening 3A to be in the open state. Then, the elevator 5 is lowered together with the lid 2A and the wafer cassette 7 to bring the portable container 2 into communication with the gas replacement device 3, and then the air supply valve 10 is opened to open an inert gas supply device (not shown). Then, an inert gas (for example, nitrogen gas) is supplied into the gas replacement device 3 and the sealed container 2. At this time, the control device 20 sends the operation command e to the suction device 25 in the exhaust pipe 9 as an initial condition to operate the suction device 25. As a result, the exhaust gas is sucked from the suction device 25 gas replacement device 3 and flows into the gas mixing chamber 17 of the gas exhaust device 16 through the exhaust pipe 9.
[0022]
Simultaneously with the operation of supplying the inert gas to the gas replacement device 3, the control device 20 sends the operation command e and the valve opening command d to each of the suction device 30 and the flow rate control valve 18 in the oxygen gas supply pipe 22. Send it out. As a result, the suction device 30 sucks oxygen gas from the oxygen gas reservoir and flows out into the gas mixing chamber 17 of the gas exhaust device 16 through the oxygen gas supply pipe 22 and the flow rate control valve 18.
The exhaust gas exhausted from the exhaust pipe 9 and the oxygen gas supplied from the oxygen gas supply pipe 22 flow out to the gas mixing chamber 17 so that their flow directions are orthogonal to each other. Will be mixed well within.
[0023]
Next, the mixed gas of the exhaust gas and the oxygen gas mixed in the gas mixing chamber 17 passes through the throttle tube 23 while being throttled from the gas mixing chamber 17, and then is larger than the throttle tube 23. 21 flows radially into the fluid radiation space A.
In this way, when the mixed gas from the gas mixing chamber 17 passes through the throttle tube 23, the oxygen gas concentration detection sensor 19 detects the oxygen gas concentration of the mixed gas passing through the throttle tube 23, and oxygen in the mixed gas An oxygen gas concentration detection signal b corresponding to the gas concentration is sent to the control device 20.
Then, the control device 20 having received the gas concentration detection signal b from the oxygen gas concentration detection sensor 19 and the oxygen gas concentration region data c set in advance or set by the concentration setter 26 and the gas concentration detection signal. For example, when the oxygen gas concentration of the mixed gas passing through the throttle tube 23 is equal to or lower than the lower limit value of the oxygen gas concentration region data c that does not affect the human body, the degree of opening of the flow control valve 18 is maximized. The valve opening command d is sent to the flow control valve 18, and the degree of opening of the flow control valve 18 gradually increases as the oxygen gas concentration moves from the lower limit value to the upper limit value of the oxygen gas concentration region data c that does not affect the human body. A valve opening command d that decreases is sent to the flow control valve 18. As a result, the flow rate control valve 18 changes the valve opening degree based on the valve opening degree command d from the control device 10, and the flow rate of oxygen gas sucked by the suction device 30 from the oxygen gas reservoir is changed. By controlling, the flow rate of the oxygen gas flowing out into the gas mixing chamber 17 is changed. As a result, the gas mixing chamber 17 is set so that the oxygen gas concentration in the mixed gas exhausted into the clean room 1 is within the oxygen gas concentration region data c in accordance with the amount of exhaust gas exhausted from the gas replacement device 3. The oxygen gas can be discharged from the oxygen gas reservoir by changing the flow rate of the oxygen gas through the suction device 30 and the flow rate control valve 18.
[0024]
The mixed gas that has passed through the throttle tube 23 from the gas mixing chamber 18 flows out radially into the fluid radiation space A in the clean chamber 16, and enters the interior from the entire surface of the filter 13 inserted in the clean chamber 16. After the dust and dust existing in the mixed gas are removed when flowing in and passing through the filter 13, the dust is discharged into the clean room 1 from the opening of the clean chamber 16. Since the oxygen gas concentration does not affect the human body, workers working in the clean room 1 can work safely and hygienically without falling into an oxygen deficiency symptom.
[0025]
After that, when a predetermined time has passed and the purity of the inert gas in the gas replacement device 3 and the sealed container 2 is increased and replaced, the air supply valve 10 and the flow rate control valve 18 are closed, and each suction device 25 is closed. , 30 is stopped and the supply of the inert gas to the gas replacement device 3 and the exhaust of the exhaust gas from the gas replacement device 3 are stopped, and then the lifting platform 5 of the lifting device 6 is moved together with the lid 2A and the wafer cassette 7 The wafer cassette 7 is housed in the airtight container 2 in an airtight manner, and the replacement of the airtight container 2 with the inert gas is completed.
[0026]
In the gas supply / exhaust system of the portable sealed container according to the embodiment of the present invention, the gas replacement device 3 and the gas exhaust device 16 are separately provided. However, the present invention is not limited to this. As shown in FIG. 2, the gas replacement device 3 and the gas exhaust device 16 may be integrally formed in series. In this case, as shown in FIG. 2, the gas mixing chamber 17 is integrally formed continuously below the gas replacement device 3, and the clean chamber 21 is provided in the gas mixing chamber 17. In addition, a check valve 27 that prevents the flow of the mixed gas from the gas mixing chamber 17 is disposed in the exhaust pipe 9 that communicates the gas replacement device 3 and the gas mixing chamber 17.
In the gas mixing chamber 17, the oxygen gas supply pipe 22 is connected to the exhaust pipe 9 in order to successfully mix the exhaust gas exhausted from the gas replacement device 3 and the oxygen gas supplied from the oxygen gas reservoir. The gas mixing chamber 17 is opened from a direction perpendicular to the flow direction a of the exhaust gas supplied into the gas mixing chamber 17, and a clean chamber 21 is provided immediately below the oxygen gas supply pipe 22.
The operation of the gas supply / exhaust system of the portable sealed container in FIG. 2 is performed in the same manner as the gas supply / exhaust system shown in FIG. In FIG. 2, the suction device 25 is not necessary because it is integrated in series and flows into the gas mixing chamber 17 with the supply flow rate of the inert gas.
[0027]
In the gas supply / exhaust system of the portable sealed container shown in FIGS. 1 and 2 of the present invention, an oxygen gas concentration detection sensor is used as the gas concentration detection means 19, but the present invention is not limited to this. A nitrogen gas concentration detection sensor that detects the concentration of nitrogen gas that is an inert gas among the mixed gases mixed in the gas mixing chamber 17 may be used.
Further, in order to promote the mixing of the exhaust gas from the gas replacement device 3 and the oxygen gas from the oxygen gas reservoir in the gas mixing chamber 17, as shown in FIG. A stirring device 24 may be provided.
Furthermore, although the filter 13 may be used conventionally, the filter 13 has a high collection rate of fine particles depending on the environment in the clean room 1 and has a performance of extremely low pressure loss due to the filter itself. A high performance filter (HEPA filter) or an ultra-high performance filter (ULPA filter) having a performance higher than that of an ultra high performance filter (HEPA filter) may be used.
Further, in the gas supply / exhaust system of the portable sealed container of FIGS. 1 and 2 according to the present invention, it has been described that the mixed gas mixed in the gas mixing chamber 17 is discharged into the clean room 1. You may make it discharge | release outside the room 1. FIG. When it is known in advance that the amount of inert gas contained in the exhaust gas exhausted from the gas replacement device 3 is small, air may be supplied by installing an air reservoir instead of the oxygen gas reservoir. .
Further, in the clean room 1 where semiconductors are manufactured, air conditioning is usually performed in order to maintain the cleanliness. Therefore, in the gas supply / exhaust system of the portable sealed container shown in FIGS. 1 and 2, the air in the clean room 1 is directly connected without connecting the oxygen gas reservoir or the air reservoir to the oxygen gas supply pipe 22. The gas may be sucked from the oxygen gas supply pipe 22 by the suction device 30 and supplied into the gas mixing chamber 17.
[0028]
【The invention's effect】
Thus, according to the gas supply and exhaust system of the portable sealed container of the present invention,
In claim 1, oxygen gas is mixed with the inert gas of the gas displacement device, and the concentration of the mixed gas after mixing is set to a predetermined concentration that does not affect the worker working in the clean room, Can be released. As a result, the worker in the clean room can work safely and safely, and the degree of freedom of arrangement in the clean room is increased.
[0029]
In the second aspect, in addition to the effect of the first aspect, the control device controls the flow rate control means based on the detection signal from the gas concentration detection means, thereby controlling the flow rate of the oxygen gas supplied to the gas mixing chamber. By changing according to the flow rate of the exhaust gas exhausted from the gas replacement device, the inert gas of the mixed gas or the oxygen gas in the gas mixing chamber so as not to affect the worker working in the clean room It can be reliably controlled to be within the concentration setting region and can be discharged into the clean room. As a result, the worker in the clean room can work safely and safely, and the degree of freedom of arrangement in the clean room is increased.
[0030]
In the third aspect, in addition to the effect of the second aspect, the gas concentration setting region of the inert gas or the oxygen gas in the mixed gas in the gas mixing chamber can be set according to the environment in the clean room.
[0031]
In the fourth aspect, in addition to the effect of the first or second aspect, the gas supply / exhaust system is compact, can be easily transported, and the space in the clean room can be used without waste. It becomes.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a gas supply / exhaust system of a portable sealed container in an embodiment of the present invention.
FIG. 2 is a longitudinal sectional view in which a gas purge station and a gas exhaust device constituting a gas supply / exhaust system of a portable sealed container according to an embodiment of the present invention are integrated.
FIG. 3 is a schematic view showing a gas supply / exhaust system of a portable sealed container proposed by the present inventor.
[Explanation of symbols]
W Semiconductor wafer 1 Clean room 2 Portable sealed container 3 Gas replacement device 4 Gas exhaust pipe 13 Filter 16 Gas exhaust device 17 Gas mixing chamber 18 Flow control valve (flow control means)
19 Oxygen gas concentration detection sensor (gas concentration detection means)
20 Control device 21 Clean room 26 Concentration setter b Oxygen gas concentration detection signal c Oxygen gas concentration region data

Claims (4)

Wherein the portable sealed container which is accommodated a semiconductor wafer sealed, and gas replacement device for replacing in said friendly transportable sealed container with an inert gas, the exhaust gas containing the inert gas exhausted from the gas exchange device In a gas supply / exhaust system for a portable sealed container comprising a gas exhaust pipe that discharges outside the gas replacement device , the exhaust gas exhausted from the gas replacement device is mixed with oxygen gas in the gas exhaust pipe. A gas supply / exhaust system for a portable sealed container, wherein a gas exhaust device that discharges the mixed gas concentration after mixing into the clean room as a predetermined concentration region that does not affect the human body is connected. The gas exhaust device includes a gas mixing chamber that mixes the exhaust gas exhausted from the gas replacement device through the gas exhaust pipe and an oxygen gas supplied from outside, and a mixed gas mixed in the gas mixing chamber. Based on gas concentration detection means for detecting the concentration of inert gas or acidity gas, flow rate control means for changing the flow rate of the oxygen gas supplied into the gas mixing chamber, and detection signals from the gas concentration detection means A control device that controls the flow rate control means so that the concentration of the inert gas or oxygen gas in the mixed gas mixed in the gas mixing chamber is within a gas concentration setting region that does not affect the human body, and The gas supply / exhaust system for a portable sealed container according to claim 1, further comprising a clean chamber for cleaning the mixed gas with a filter and discharging the mixed gas. 2. The gas supply / exhaust system for a portable sealed container according to claim 1, wherein a concentration setter capable of changing the gas concentration setting region is connected to the control device. The gas supply / exhaust system for a portable sealed container according to claim 1 or 2, wherein the gas replacement device and the gas exhaust device are integrally formed.

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