TWI821138B - Equipment front-end module (EFEM) - Google Patents

Abstract

The present invention is an equipment front-end module (EFEM), the subject of which is to make it easier for inert gas to flow vertically in a transfer chamber and to make it less likely to raise dust. The solution is that the EFEM system includes: a frame (2) that constitutes the transfer chamber inside, and a support plate (37) above the transfer chamber in order to form an FFU installation chamber (42) inside the frame (2), and in order to A supply pipe (47) that supplies nitrogen to the FFU installation chamber (42), and three fans are arranged so as to cover the communication ports (37a) formed in the support plate (37). The supply pipe (47) has three supply ports (47a) dispersedly arranged in the FFU installation chamber (42).

Description

Equipment front-end module (EFEM)

The present invention relates to an EFEM (Equipment Front End Module) that supplies inert gas to a closed transfer chamber and can be replaced with an inert gas environment.

Patent Document 1 has a loading port that contains a FOUP (Front-Opening Unified Pod) that accommodates wafers (semiconductor substrates) and is connected to an opening provided on the front wall and is closed to form a The frame of the transfer chamber for transferring wafers; the EFEM that transfers wafers between the processing equipment that performs specific processing on the wafers and the FOUP are described.

In the past, the influence of oxygen, moisture, etc. in the transfer chamber on semiconductor circuits manufactured on wafers has been small. However, in recent years, as semiconductor circuits have become more miniaturized, these effects have become more significant. Therefore, the EFEM described in Patent Document 1 is configured so that the transfer chamber is filled with nitrogen as an inert gas. Specifically, the EFEM system has a circulation flow path composed of a transfer chamber and a gas return path for circulating nitrogen inside the frame, a gas supply means for supplying nitrogen to the upper space of the gas return path, and a gas supply means arranged in the gas return path. A plurality of fans are used to send the inert gas out of the transfer chamber in the upper space of the gas return path, and a gas discharge means is used to discharge nitrogen from the lower part of the gas return path. Nitrogen is appropriately supplied and discharged in response to changes in the oxygen concentration in the circulation flow path. Through this, the transfer chamber can be maintained in a nitrogen atmosphere. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2015-146349

[Problem to be solved by the invention]

However, in the EFEM described in the above-mentioned Patent Document 1, the gas supply means is connected to the upper space of the gas return path, and the inert gas is supplied from the connection point, that is, one supply port. In the upper space, The pressure on the suction side of the fan is uneven among the fans, and the supply amount from each fan to the transfer chamber is uneven. That is, when inert gas is supplied from one side of the arrangement direction of the plurality of fans, a sufficient amount of inert gas is supplied to one fan, but the supply of inert gas to the fan on the other side is limited. The quantity is less than one side. That is, in the upper space, the pressure on the suction side of one fan becomes larger than that of the other fan, and the supply amount of the inert gas from each fan to the transfer chamber becomes uneven. As a result, the air flow of the inert gas in the transfer chamber is disrupted, causing a problem that dust is easily raised.

Therefore, an object of the present invention is to provide an EFEM that can easily flow inert gas vertically into a transfer chamber and can hardly raise dust. [To solve the problem]

The EFEM system of the present invention includes a frame that connects a loading port to an opening provided in a partition and locks it, and has a transfer chamber for transferring substrates inside, and a substrate that is disposed in the transfer chamber to transfer the substrates. A conveying device, and an inert gas supply means for supplying inert gas to the inert gas in the above-mentioned upper space, and an inert gas supply means provided in the above-mentioned frame, and a partition member is provided above the above-mentioned transfer chamber in order to form an upper space, and is formed in the above-mentioned partition. A member, a plurality of communication openings connecting the transfer chamber and the upper space, and each of the communication openings is arranged to cover the communication openings, and the inert gas in the upper space is transferred to the plurality of transfer chambers through the communication openings. an air blower, a gas suction port provided at the lower part of the transfer chamber to suck inert gas in the transfer chamber, and a gas return path for returning the inert gas sucked from the gas suction port to the upper space, and Gas exhaust means for exhausting the gas in the transfer chamber. Furthermore, the inert gas supply means has a plurality of supply ports dispersedly arranged in the upper space for supplying the inert gas.

Through this, the inert gas supplied from the inert gas supply means to the upper space can be distributed and supplied from a plurality of supply ports. Therefore, the inert gas can be uniformly supplied to the upper space throughout the entire space, and the pressure unevenness on the suction sides of the plurality of air blowers in the upper space becomes smaller. Accordingly, unevenness in the supply amount of the inert gas from each air blower to the transfer chamber is less likely to occur. As a result, the inert gas easily flows vertically in the transfer chamber and becomes less likely to raise dust.

In the present invention, the supply port is located in any one of the partition wall and the partition member of the frame that separates the upper space and the external space, and is oriented toward a range closest to the supply port to supply the inert gas. The one that is composed is better. Through this, the inert gas supplied from the supply port contacts either the partition member or the partition wall, and its force is weakened, and the inert gas flows along either the partition member or the partition wall. Therefore, the air flow flowing from the gas return path to the upper space of the air blower becomes less likely to be disrupted, and the pressure unevenness on the suction sides of the plurality of air blowers in the upper space becomes smaller. Accordingly, uneven supply of the inert gas from each air blower to the transfer chamber is further suppressed.

In addition, in the present invention, a plurality of the gas suction ports are provided in the lower part of the transfer chamber, and the gas return path has a plurality of first flow paths extending upward from each of the plurality of gas suction ports, It is preferable that the second flow path connected to the plurality of first flow paths further has a delivery port for sending the gas in the second flow path out of the upper space. Through this, the gas from the transfer chamber passes through the plurality of first flow paths, temporarily flows into the second flow paths, and then flows into the upper space. In this way, by temporarily flowing the gas from the plurality of first flow paths to the second flow path, it becomes possible to absorb the uneven flow rate of the gas between the plurality of first flow paths. Therefore, compared with when the gas is directly sent to the upper space from each first flow path, the amount of gas sent from the outlet is more stable, and the uneven supply amount of the inert gas from each air blower to the transfer chamber is further suppressed.

In addition, in the present invention, the second flow path extends along the arrangement direction of the plurality of first flow paths, and the delivery ports are each arranged at two adjacent first flow paths in the arrangement direction. The one between the flow paths is better. Through this, the amount of gas delivered from the outlet to the upper space becomes more stable, and uneven supply of inert gas from each air blower to the transfer chamber is further suppressed.

Furthermore, in the present invention, it is preferable that the outlet is disposed at a position sandwiching the air blower between the outlet and the supply port in an intersecting direction intersecting the arrangement direction of the plurality of air blowers. Through this, the air flow flowing from the gas return path to the upper space of the air blower becomes less likely to be disrupted, further suppressing uneven supply of the inert gas from each air blower to the transfer chamber.

In addition, in another aspect, the EFEM of the present invention is provided with a frame that connects the loading port to an opening provided in the partition and locks it, and includes a transfer chamber for transferring the substrate inside, and is provided in the frame. In order to form a partition member between the upper space above the transfer chamber, a plurality of communication ports are formed on the partition member to connect the transfer chamber and the upper space, and the communication ports are provided in order to transmit the gas in the upper space. A plurality of air blowers in the transfer chamber, a plurality of gas suction ports provided at the lower part of the transfer chamber to suck gas in the transfer chamber, and a device that returns the gas sucked from each of the gas suction ports to the upper space. Gas return path. Furthermore, the gas return path includes a plurality of first flow paths extending from the plurality of gas suction ports, and is connected to the plurality of first flow paths so that the gas flows from the first flow paths, The gas is sent to the second flow path of the upper space.

When passing through this, the gas from the transfer chamber passes through the plurality of first flow paths, temporarily flows into the second flow paths, and then flows to the upper space. In this way, by temporarily flowing the gas from the plurality of first flow paths to the second flow path, it becomes possible to absorb the uneven flow rate of the gas between the plurality of first flow paths. Therefore, compared with when the gas is directly sent to the upper space from each first flow path, the amount of gas sent from the outlet is more stable, and the uneven supply amount of gas from each air blower to the transfer chamber is suppressed.

In addition, in the present invention, the second flow path extends in a direction intersecting the extending direction of the first flow path, and the gas system flowing in the gas return path flows from the first flow path. It is preferable to change the direction of the air flow when entering the second flow path, and also to change the direction of the air flow when flowing from the second flow path to the upper space. Through this, the second flow path can serve as a means to relax the flow of gas in the extending direction of the first flow path. Therefore, compared with the case where the direction of the air flow is not changed from the first flow path to the upper space and the gas flows directly into the upper space, it can be considered that the air flow in the upper space is less likely to be disturbed.

In addition, in the present invention, there is a base portion at a fixed position, a conveying portion disposed above the base portion, and conveying the substrate, and a substrate conveying device disposed in the conveying chamber. The conveying chamber is The installation object is disposed below the conveying range of the substrate through the conveyance part, and the gas suction port is disposed at a position that does not overlap with any of the base part and the installation object when viewed from the vertical direction. Can. [Effects of the invention]

When the EFEM of the present invention is used, the inert gas can be uniformly supplied to the upper space throughout the entire space, and the pressure unevenness on the suction side of the plurality of air blowers in the upper space becomes smaller. Accordingly, unevenness in the supply amount of the inert gas from each air blower to the transfer chamber is less likely to occur. As a result, the inert gas easily flows vertically in the transfer chamber and becomes less likely to raise dust.

Hereinafter, an EFEM 1 according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 8 . However, for the convenience of explanation, the direction shown in Figure 1 is regarded as the front, rear, left and right directions. That is, in this embodiment, the direction in which the EFEM (Equipment Front End Module) 1 and the substrate processing apparatus 6 are arranged is regarded as the front-rear direction, the EFEM 1 side is regarded as the front, and the substrate processing apparatus 6 side is regarded as the rear. In addition, the direction orthogonal to the front-rear direction and in which a plurality of loading ports 4 are arranged is defined as the left-right direction. In addition, the direction orthogonal to both the front-rear direction and the left-right direction is defined as the up-down direction.

(Schematic structure of EFEM and surrounding areas) First, the schematic structure of EFEM1 and its surroundings will be described using FIGS. 1 and 2 . FIG. 1 is a plan view showing the schematic configuration of the EFEM 1 and its surroundings according to this embodiment. Figure 2 is a diagram showing the electrical structure of EFEM1. As shown in FIG. 1 , the EFEM1 system includes a frame 2 , a transfer robot arm 3 (substrate transfer device), three loading ports 4 , and a control device 5 . Behind the EFEM 1 is a substrate processing device 6 that performs specific processing on the wafer W (substrate). The EFEM 1 transfers the wafer W between the FOUP (Front-Opening Unified Pod) 100 placed in the loading port 4 and the substrate processing apparatus 6 via the transfer robot arm 3 arranged in the housing 2 . The FOUP 100 is a container that can accommodate a plurality of wafers W arranged in the up-and-down direction, and is provided with an openable and closable lid 101 at the rear end (the end on the frame 2 side in the front-rear direction). The FOUP 100 is transported via a well-known OHT (overhead traveling unmanned transport vehicle: not shown), for example. Between OHT and load port 4, FOUP100 is exchanged.

The frame 2 is configured to connect the three loading ports 4 and the substrate processing apparatus 6 . A transfer chamber 41 is formed inside the frame 2 so as to be slightly sealed from the outside space so as to transport the wafer W without being exposed to outside air. When EFEM1 is activated, the transfer chamber 41 is filled with nitrogen. However, in this embodiment, the transfer chamber 41 is filled with nitrogen, but if it is an inert gas, it may maintain a composition other than nitrogen (for example, argon, etc.). The frame 2 is configured to circulate nitrogen in an internal space including the transfer chamber 41 (details will be described later). In addition, an openable and closable door 2 a is attached to the rear end of the frame 2 , and the transfer chamber 41 is connected to the substrate processing apparatus 6 via the door 2 a.

The transfer robot arm 3 is disposed in the transfer chamber 41 and transfers the wafer W. The transfer robot arm 3 has a fixed-position base portion 90 (see FIG. 3 ), and an arm mechanism 70 (transfer portion, see FIG. 3 ) disposed above the base portion 90 to hold and transfer the wafer W. and the robot arm control unit 11 (see Figure 2). The transfer robot arm 3 mainly performs the operation of taking out the wafer W in the FOUP 100 and delivering it to the substrate processing apparatus 6 , or receiving the wafer W processed by the substrate processing apparatus 6 and returning it to the FOUP 100 .

The load port 4 is configured to load the FOUP 100 (see FIG. 7 ). As shown in FIGS. 1 and 5 , the plurality of loading ports 4 are arranged in the left and right directions along the partition wall 33 on the front side of the frame 2 . Each loading port 4 is closed in the space 51 at the rear end (see FIG. 7 ), and has three openings 33a1 formed in the partition wall 33 of the frame 2 (see FIG. 4 ). As a result, the transfer chamber 41 is configured as a substantially closed space within the housing 2 . In addition, loading port 4 can replace the ambient air in FOUP100 with nitrogen. The rear end of the loading port 4 is provided with a door 4a which is a part of an opening and closing mechanism 54 to be described later. The door 4a is opened and closed via the door driving mechanism 55 (part of the opening and closing mechanism 54). The door 4a is configured to unlock the cover 101 of the FOUP 100 and hold the cover 101. When the door 4a is opened with the lid 101 unlocked and the door 4a is opened by the door driving mechanism 55, the lid 101 is opened. Through this, the wafer W in the FOUP 100 can be taken out via the transfer robot arm 3 . In addition, the wafer W can be stored in the FOUP 100 via the transfer robot arm 3 .

As shown in Figure 2, the control device 5 is electrically connected to the robot arm control part 11 of the transport robot arm 3, the loading port control part 12 of the loading port 4, and the control part (not shown) of the substrate processing device 6, and Communicates with the control unit. In addition, the control device 5 is electrically connected to the oxygen concentration meter 85, the pressure gauge 86, the hygrometer 87, etc. installed in the frame 2, and receives the measurement results of these measuring devices to grasp the relevant information about the frame 2. Information about the internal environment. In addition, the control device 5 is electrically connected to a supply valve 112 and a discharge valve 113 (described later), and by adjusting the opening of these valves, the nitrogen ambient gas in the frame 2 can be appropriately adjusted.

As shown in FIG. 1 , the substrate processing apparatus 6 has, for example, a load lock vacuum chamber 6 a and a processing chamber 6 b. The load lock vacuum chamber 6a is connected to the transfer chamber 41 via the door 2a of the housing 2, and is a chamber for temporarily waiting for the wafer W. The processing chamber 6b is connected to the load lock vacuum chamber 6a via the door 6c. In the processing chamber 6b, specific processing is performed on the wafer W via a processing mechanism (not shown).

(Frame and its internal composition) Next, the structure of the frame 2 and its interior will be described using FIGS. 3 to 6 . Figure 3 is a front view of the frame 2 when viewed from the front. FIG. 4 is a cross-sectional view along line IV-IV shown in FIG. 3 . FIG. 5 is a cross-sectional view along line V-V shown in FIG. 3 . FIG. 6 is a cross-sectional view along line VI-VI shown in FIG. 3 . However, illustration of the partition wall is omitted in FIGS. 3 and 6 . In addition, in FIG. 5 , the illustration of the transport robot arm 3 and the like is omitted, and the loading port 4 is shown as a two-point chain line.

The frame 2 as a whole has a substantially rectangular parallelepiped shape. As shown in Figures 3 to 5, the frame 2 system has columns 21 to 26, a connecting pipe 27, and partition walls 31 to 36. The partition walls 31 to 36 are attached to the columns 21 to 26 extending in the vertical direction, and the internal space of the frame 2 (the transfer chamber 41 and the FFU installation chamber 42) is configured to be somewhat airtight from the outside space.

More specifically, as shown in FIG. 4 , in the front end of the frame 2 , the columns 21 to 24 are arranged in sequence while being isolated from each other from the left to the right. That is, the four pillars 21 to 24 are arranged along the left and right directions. In addition, the columns 21 to 24 are erected along the up-and-down direction as shown in FIG. 3 . The columns 21 and 24 are composed of first parts 21b and 24b arranged on the lower side and second parts 21c and 24c arranged on the upper side. The first parts 21b and 24b are erected on the partition wall 31, and their upper ends are connected to the connecting pipe 27. In addition, the columns 22 and 23 are also erected on the partition wall 31, and their upper ends are connected to the connecting pipe 27. The lengths of the first portions 21b, 24b and the columns 22, 23 in the up-down direction are approximately the same length. The second parts 21c and 24c are connected to the connecting pipe 27 and are erected at a position overlapping the first parts 21b and 24b in the vertical direction. Two columns 25 and 26 are arranged vertically on the left and right sides of the rear end of the frame 2 along the up and down direction. The connecting pipe 27 extends in the left-right direction (the direction in which the four columns 21 to 24 are arranged), and is connected to the four columns 21 to 24 with each other.

As shown in FIG. 3 , a partition wall 31 is arranged at the bottom of the frame 2 and a partition wall 32 is arranged at the top of the ceiling. As shown in FIG. 4 , a partition wall 33 is arranged at the front end, a partition wall 34 is arranged at the rear end, a partition wall 35 is arranged at the left end, and a partition wall 36 is arranged at the right end. The partition wall 33 is formed with the aforementioned three openings 33a1. These three openings 33a1 are arranged between the four columns 21 to 24 in the left-right direction, and are closed through the base 51 of the loading port 4. The right end portion of the frame 2 is provided with a placement portion 83 (see FIG. 3 ) in which a positioner 84 to be described later is arranged. The positioner 84 and the placing part 83 are also accommodated inside the frame 2 (see FIG. 4 ).

As shown in FIG. 5 , in the upper portion of the frame 2 , a support plate 37 (spacer member) extending in the horizontal direction is arranged on the rear end side of the connecting pipe 27 . Through this, the inside of the frame 2 is divided into the aforementioned transfer chamber 41 and the FFU installation room 42 formed above the transfer chamber 41 . That is, the FFU installation chamber 42 is formed as an upper space above the transfer chamber 41 in the internal space of the frame 2 via the support plate 37 .

Three FFU (fan filter units) 44 to be described later are arranged in the FFU installation room 42. Three communication openings 37 a are formed in the center portion of the support plate 37 in the front-rear direction, facing the up-down direction of the FFU 44 , for connecting the transfer chamber 41 and the FFU installation chamber 42 . These three communication ports 37a are arranged in an array along the left-right direction as shown in FIG. 6 . In addition, three communication ports 37a are arranged in the left-right direction between the four pillars 21 to 24. However, the partition walls 33 to 36 of the frame 2 are divided into a lower wall for the transfer chamber 41 and an upper wall for the FFU installation chamber 42 (for example, refer to the partition walls 33a and 33b at the front end and the partition wall at the rear end in FIG. 5 34a, 34b). The number of revolutions of each FFU 44 is determined in advance so that the air flow velocity in the conveyance range 200 described below becomes a desired value. The airflow velocity in the conveyance range 200 is less than 1m/s, ideally 0.1m/s~0.7m/s, and more ideally 0.2m/s~0.6m/s. The rotation of each FFU is determined according to the target value. Count.

Next, the internal structure of the housing 2 will be described. Specifically, the structure for circulating nitrogen in the housing 2 and its surrounding structure, as well as the equipment arranged in the transfer chamber 41 will be described.

The structure for circulating nitrogen in the frame 2 and its peripheral structure will be explained using FIGS. 3 to 6 . As shown in FIG. 5 , a circulation path 40 for circulating nitrogen is formed inside the frame 2 . The circulation path 40 is configured through the transfer chamber 41, the FFU installation chamber 42, and the return path 43 (gas return path). In the circulation path 40, clean nitrogen is sent downward from the FFU installation chamber 42 through each communication port 37a. After reaching the lower end of the transfer chamber 41, it rises through the return path 43 and returns to the FFU installation chamber. 42 (refer to the arrow in Figure 5). Detailed description below.

As shown in FIGS. 5 and 6 , the FFU installation chamber 42 is provided with three FFU 44 arranged on the support plate 37 and three chemical filters 45 arranged on the FFU 44 . As shown in FIG. 5 , each FFU 44 has a fan 44a (air blower) and a filter 44b, and is arranged on the support plate 37 to form a covered communication port 37a. As shown by the arrow in FIG. 6 , the FFU 44 sucks the nitrogen in the FFU installation chamber 42 from around the FFU 44 through the fan 44 a and sends it out to the bottom, and at the same time removes dust containing nitrogen through the filter 44 b (not shown in the figure). ). The chemical filter 45 is configured, for example, to remove active gas and the like introduced into the circulation path 40 from the substrate processing apparatus 6 . The nitrogen purified by the FFU 44 and the chemical filter 45 is sent from the FFU installation chamber 42 to the transfer chamber 41 through the communication port 37 a formed in the support plate 37 . The nitrogen sent out of the transfer chamber 41 forms a laminar flow and flows downward.

The return path 43 is formed in the columns 21 to 24 (the bollard 23 in FIG. 5 ) and the connecting pipe 27 arranged at the front end of the frame 2 . The interiors of the first portions 21b and 24b of the columns 21 and 24, the columns 22 and 23, and the connecting tube 27 are hollow, and spaces 21a to 24a and 27a through which nitrogen can flow to each other are formed (see Fig. 4). The first portions 21b and 24b of the columns 21 and 24 are as shown in Fig. 4, and their left and right widths are larger than those of the columns 22 and 23. That is, the planar dimensions of the spaces 21a and 24a (the first flow path) (that is, the opening areas of the first portions 21b and 24b) are larger than those of the spaces 22a and 23a (the opening areas of the columns 22 and 23). In addition, the spaces 21a to 24a (first flow paths) are formed to extend in the up and down direction, and extend from the lower ends of the columns 21 to 24 to the position of the connecting pipe 27 .

The connecting pipe 27 is arranged at the front end of the frame 2 . The space 27a (second flow path) of the connecting pipe 27 extends in the left-right direction. In addition, as shown in FIGS. 5 and 6 , the lower surface of the connecting pipe 27 is formed with communication ports 27b to 27e for communicating the spaces 21a to 24a and the space 27a with each other. In addition, as shown in FIG. 6 , three delivery ports 27f to 27h opening toward the FFU installation chamber 42 (that is, upward) are formed on the upper surface of the connecting pipe 27 . These three delivery ports 27f to 27h are arranged between the four pillars 21 to 24 in the left and right direction, and have a long rectangular plan shape in the left and right direction. In addition, three delivery ports 27f to 27h are arranged at the front end of the frame 2. In this way, the connecting pipe 27 is configured so that the nitrogen flowing in from the four spaces 21a to 24a can be once combined and then sent out to the FFU installation chamber 42 from the three delivery ports 27f to 27h. When nitrogen flows from the spaces 21a to 24a to the space 27a, the direction of the air flow changes from above to the left and right directions. When nitrogen flows from the space 27a through the delivery ports 27f to 27h into the FFU installation chamber 42, the direction of the air flow changes. Then it changes from the left and right direction to the top. The return path 43 is formed through such spaces 21a to 24a and 27a. In addition, the three delivery ports 27f to 27h are arranged in positions overlapping the FFU 44 in the front-rear direction. That is, they are respectively connected to the delivery ports 27f to 27h and the FFU 44 in the front and rear directions. Furthermore, the three delivery ports 27f to 27h are formed elongated in the left-right direction and have a relatively large opening area. Therefore, the flow of the gas sent to the FFU installation chamber 42 from the respective delivery ports 27f to 27h becomes gentle, and the pressure unevenness on the suction side (upper side) of the three FFUs 44 becomes smaller. However, as shown in FIG. 5 , the gas system sent out from the sending outlets 27f to 27h to the FFU installation chamber 42 passes between the partition wall 33 and the FFU 44 and flows upward.

The return path 43 will be described in more detail with reference to FIG. 5 . However, FIG. 5 shows column 23, but the same applies to the first portions 21b, 24b and column 22 of other columns 21, 24. An introduction pipe 28 is installed at the lower end of the column 23 to facilitate the flow of nitrogen in the transfer chamber 41 into the return path 43 (space 23a). The introduction duct 28 is similarly installed on the other columns 21, 22, and 24. However, since the columns 21 and 24 are formed wider than the column 23 in the left-right direction, the installed introduction duct 28 is also formed wider, but other than that, they have the same structure. The introduction duct 28 is formed with an opening 28 a so that nitrogen reaching the lower end of the transfer chamber 41 can flow into the return path 43 . That is, the opening 28 a is a gas suction port that sucks nitrogen in the transfer chamber 41 to the return path 43 . In addition, the opening 28a is configured to face downward. Therefore, the gas reaching the partition wall 31 from above can be smoothly inhaled without disrupting the flow of the gas from above. Furthermore, the gas that can be sucked in through the opening 28a flows upward without changing the direction of the gas flow.

The upper portion of the introduction duct 28 is formed with an enlarged portion 28 b that spreads toward the rear as it goes downward. In the introduction duct 28, a fan 46 is arranged below the enlarged portion 28b. The fan 46 is driven by a motor (not shown), sucks the nitrogen that reaches the lower end of the transfer chamber 41 into the return path 43 (space 23a in FIG. 5 ), sends it upward, and returns the nitrogen to the FFU installation. Room 42. The nitrogen returned to the FFU installation chamber 42 is sucked from the upper surface of the chemical filter 45 to the FFU 44 side, is cleaned through the FFU 44 or the chemical filter 45, and is sent out to the transfer chamber 41 through the communication port 37a again. As a result, nitrogen can be circulated in the circulation path 40 .

In addition, as shown in FIG. 3 , a supply pipe 47 for supplying nitrogen into the FFU installation chamber 42 (circulation path 40 ) is arranged at the upper rear end of the FFU installation chamber 42 (that is, the rear end of the frame 2 ). The supply pipe 47 is connected to an external pipe 48 connected to the nitrogen supply source 111 . A supply valve 112 capable of changing the supply amount of nitrogen per unit time is provided in the middle of the external pipe 48 . The inert gas supply means is configured through the supply pipe 47, the external pipe 48, the supply valve 112 and the supply source 111. However, when the inert gas supply line is installed in a factory or the like, the supply line and the supply pipe 47 may be connected. Therefore, the inert gas supply means may be configured from the supply pipe 47 only.

As shown in FIGS. 3 and 6 , the supply pipe 47 extends in the left-right direction and has three supply ports 47 a formed therein. The three supply ports 47a are spaced apart from each other in the left-right direction, and nitrogen is supplied from the supply pipe 47 into the FFU installation chamber 42. As shown in FIGS. 5 and 6 , these three supply ports 47 a are formed at the lower end of the supply pipe 47 , and form a range 37 b opposite to the supply pipe 47 of the support plate 37 in the up and down direction (that is, to the support plate 37 ). The distance between the supply port 47a of 37 is the shortest range) and is configured to supply nitrogen. In addition, the three supply ports 47a are arranged in the left and right direction in the same positional relationship as the center of the FFU 44. Through this, the three supply ports 47a are arranged in the front-rear direction at a position sandwiching the fan 44a between the delivery ports 27f to 27h.

When nitrogen is supplied to the FFU installation chamber 42 from the three supply ports 47a of the supply pipe 47, since the three supply ports 47a are dispersedly arranged in the FFU installation chamber 42, nitrogen is evenly supplied to the entire FFU installation chamber 42. . For example, when nitrogen is directly supplied into the FFU installation chamber 42 from a supply port of the external pipe 48 connected to the right end of the frame 2, the pressure in the right portion of the FFU installation chamber 42 increases. That is, the pressure on the suction side of the rightmost FFU 44 is larger than that of the other two FFU 44 . In this way, when large unevenness occurs in the pressure on the suction side of the FFU 44 , unevenness is likely to occur in the supply amount of nitrogen from the three FFU 44 to the transfer chamber 41 . However, in this embodiment, since nitrogen is supplied from three supply ports 47a that are isolated from each other and arranged in the left and right directions, the pressure unevenness on the suction sides of the three FFUs 44 becomes smaller. Accordingly, the supply amount of nitrogen from the three FFUs 44 to the transfer chamber 41 becomes stable, and the nitrogen sent to the transfer chamber 41 forms a laminar flow and flows downward.

In addition, as shown in FIG. 5 , a discharge pipe 49 for discharging gas in the circulation path 40 is connected to the lower end of the loading port 4 . However, as will be described later, the loading port 4 is connected to the storage chamber 60 in which the door driving mechanism 55 is stored through the slit 51 b formed in the base 51 (see FIG. 7 ). Furthermore, the discharge pipe 49 is connected to the storage chamber 60 . The discharge pipe 49 is connected to an exhaust port (not shown), for example, and is provided with a discharge valve 113 at an intermediate position thereof that can change the discharge amount of gas in the circulation path 40 per unit time. Gas discharging means is formed through the discharge pipe 49 and the discharge valve 113 .

The supply valve 112 and the discharge valve 113 are electrically connected to the control device 5 (see FIG. 2 ). Through this, nitrogen can be supplied and discharged appropriately to the circulation path 40 . For example, when EFEM1 is started (for example, including starting after maintenance of EFEM1, etc.), the oxygen concentration in the circulation path 40 increases. Nitrogen is supplied to the circulation path from the supply source 111 through the external pipe 48 and the supply pipe 47. 40. By discharging the gas (gas: including nitrogen, oxygen, etc.) in the circulation path 40 and the storage chamber 60 through the discharge pipe 49, the oxygen concentration can be reduced. That is, the circulation path 40 and the storage chamber 60 can be replaced with nitrogen ambient gas. However, when EFEM1 is activated and the oxygen concentration in the circulation path 40 increases, the oxygen concentration can be reduced by temporarily supplying more nitrogen to the circulation path 40 and discharging oxygen together with the nitrogen through the discharge pipe 49 . For example, in the EFEM 1 that circulates nitrogen, the leakage of nitrogen from the circulation path 40 to the outside is suppressed. In order to reliably suppress the intrusion of the atmosphere from the outside into the circulation path 40, the pressure within the circulation path 40 must be reduced. The external pressure is maintained slightly higher. Specifically, it is in the range of 1Pa(G)~3000Pa(G), and ideally it is 3Pa(G)~500Pa(G), and more preferably 5Pa(G)~100Pa(G). Therefore, when the pressure in the circulation path 40 deviates from a specific range, the control device 5 adjusts the nitrogen discharge flow rate by changing the opening of the discharge valve 113 so that the pressure reaches a specific target pressure. In this way, the nitrogen supply flow rate is adjusted based on the oxygen concentration, and the nitrogen discharge flow rate is adjusted based on the pressure, thereby suppressing the oxygen concentration and pressure. In this embodiment, the pressure difference is adjusted to 10 Pa (G).

Next, the equipment and the like arranged in the transfer chamber 41 will be described using FIGS. 3 and 4 . As shown in FIGS. 3 and 4 , the above-mentioned transfer robot arm 3 , a control unit storage box 81 , a measurement device storage box 82 , and a positioner 84 are arranged in the transfer chamber 41 . The control unit storage box 81 is, for example, provided on the left side of the base portion 90 of the transport robot arm 3 (see FIG. 3 ), and is located farther than the transport range 200 in which the wafer W is transported via the arm mechanism 70 (see FIG. 3 ). below. The control unit storage box 81 stores the above-described robot arm control unit 11 or loading port control unit 12. The measuring device storage box 82 is, for example, disposed on the right side of the base portion 90 and below the transport range 200 of the arm mechanism 70 . The measuring device storage box 82 is configured to accommodate the above-mentioned measuring devices such as the oxygen concentration meter 85, the pressure meter 86, the hygrometer 87, etc. (see FIG. 2). The control unit storage box 81 and the measurement device storage box 82 correspond to the installations of the present invention. The above-mentioned introduction duct 28 (see FIG. 4 ) is arranged in front of the base portion 90 , the control unit storage box 81 , and the measurement device storage box 82 . That is, the opening 28a is disposed at a position where none of the base portion 90, the control unit storage box 81, and the measurement device storage box 82 overlap when viewed from the up and down direction (vertical direction) (see FIG. 4, FIG. 5).

The positioner 84 is configured to detect how much the wafer W is held by the arm mechanism 70 (see FIG. 3 ) of the transfer robot arm 3 and is shifted from the target holding position. For example, within the FOUP 100 (see FIG. 1 ) transported via the above-mentioned OHT (not shown), the wafer W may move slightly. Therefore, the transfer robot 3 temporarily places the unprocessed wafer W taken out from the FOUP 100 on the positioner 84 . The positioner 84 measures how far the wafer W is held by the transfer robot 3 from the target holding position, and sends the measurement result to the robot control unit 11 . The robot arm control unit 11 corrects the holding position via the arm mechanism 70 based on the above measurement results, controls the arm mechanism 70 to hold the wafer W at the target holding position, and transports the wafer W to the load lock vacuum chamber 6 a of the substrate processing apparatus 6 . Thereby, the wafer W can be processed normally by the substrate processing apparatus 6 .

(Construction of loading port) Next, the structure of the loading port will be described below with reference to FIGS. 7 and 8 . Figure 7 is a side cross-sectional view of the loading port showing the state of the door being closed. Figure 8 is a side cross-sectional view of the loading port showing the state of the door being opened. However, FIGS. 7 and 8 illustrate a state in which the outer cover 4b (see FIG. 5 ) is removed and located below the mounting table 53 .

As shown in FIG. 7 , the loading port 4 has a plate-shaped base 51 standing upright in the up-down direction, and a horizontal base 52 formed to protrude forward from the center portion of the base 51 in the up-down direction. A mounting base 53 for mounting the FOUP 100 is provided above the horizontal base 52 . The mounting base 53 is in a state where the FOUP 100 is mounted, and is movable in the front-rear direction via a mounting base driving unit (not shown).

The base 51 forms part of the partition wall 33 that isolates the transfer chamber 41 from the outside space. The base 51 has a substantially rectangular planar shape that is long in the up and down direction when viewed from the front. In addition, the base 51 is formed with a window portion 51 a at a position facing the FOUP 100 placed therein in the front-rear direction. In addition, the base 51 is formed in a position lower than the horizontal base 52 in the up-down direction, and is formed with a slit 51 b extending in the up-down direction in which the support frame 56 described later can move. The slit 51b is formed in a state where the support frame 56 penetrates the base 51 and is only movable up and down, and the opening width in the left and right directions becomes smaller. Therefore, dust in the storage chamber 60 is less likely to invade into the transfer chamber 41 through the gap 51b.

The loading port 4 has an opening and closing mechanism 54 capable of opening and closing the cover 101 of the FOUP 100 . The opening and closing mechanism 54 includes a door 4a capable of closing the window portion 51a, and a door driving mechanism 55 for driving the door 4a. The door 4a is configured so that the window portion 51a can be closed. In addition, the door 4a is configured to unlock the cover 101 of the FOUP 100 and hold the cover 101. The door driving mechanism 55 includes a support frame 56 for supporting the door 4a, a movable member 58 that moves the support frame 56 in the front-rear direction by the slide support means 57, and this movable member 58 with respect to the base. 51 is a slide rail 59 that is supported movable in the up and down direction.

The support frame 56 is a slightly curved plate-like member that supports the lower portion of the rear portion of the door 4 a and extends downward, and then protrudes toward the front of the base 51 through the slit 51 b provided in the base 51 . In addition, in order to support the slide support means 57 of the support frame 56, the movable member 58 and the slide rail 59 are provided in front of the base 51. That is, the driving point for moving the door 4 a is outside the frame 2 and is accommodated in the storage chamber 60 provided below the horizontal base 52 . The storage chamber 60 is composed of a horizontal base 52, surrounded by a substantially box-shaped lid 61 and a base 51 extending downward from the horizontal base 52, and is in a substantially sealed state.

The above-mentioned discharge pipe 49 is connected to the bottom wall 61a of the cover 61. That is, the storage chamber 60 and the discharge pipe 49 are connected. In this embodiment, the storage chamber 60 and the discharge pipe 49 are connected to any one of the three loading ports 4 . Through this, the gas in the circulation path 40 can be discharged from the discharge pipe 49 through the storage chamber 60 . When the gas is discharged from the discharge pipe 49, the dust present in the storage chamber 60 may be discharged simultaneously with the gas. In addition, in the storage chamber 60, a fan 62 is provided on the bottom wall 61a to face the discharge pipe 49. In this way, disposing the fan 62 in the storage chamber 60 can suppress the dust from being raised and at the same time, it is easy to discharge gas from the storage chamber 60 to the exhaust pipe 49 . If a fan is provided to send the air in the transfer chamber 41 toward the storage chamber 60 , it is easy to cause confusion in the air flow in the transfer chamber 41 and easily raise dust in the transfer chamber 41 . However, in this embodiment , since the fan 62 is disposed in the storage chamber 60, the dust in the transfer chamber 41 can be suppressed from being raised.

Next, the opening and closing operations of the cover 101 and the door 4a of the FOUP 100 will be described below. First, as shown in FIG. 7 , in a state of being isolated from the base 51 , the mounting base 53 is moved toward the rear, so that the FOUP 100 placed on the mounting base 53 comes into contact with the cover 101 and the door 4 a. At this time, the door 4a of the opening and closing mechanism 54 unlocks the cover 101 of the FOUP 100 and holds the cover 101.

Next, as shown in FIG. 8 , the support frame 56 is moved toward the rear. Through this, the door 4a and the cover 101 move to the rear. By doing this, when the cover 101 of the FOUP 100 is opened, the door 4a is opened, and the transfer chamber 41 of the frame 2 and the FOUP 100 are connected.

Next, as shown in FIG. 8 , the support frame 56 is moved downward. Through this, the door 4a and the cover 101 move downward. By doing this, the FOUP 100 is widely opened as a transfer entrance, and the wafer W can be moved between the FOUP 100 and the EFEM 1 . However, in order to close the cover 101 and the door 4a, the opposite operation to the above may be performed. In addition, a series of operations of the load port 4 are controlled via the load port control unit 12 .

As described above, when passing through the EFEM 1 of this embodiment, the three supply ports 47a are dispersedly arranged in the FFU installation chamber 42, so that nitrogen can be evenly supplied to the entire FFU installation chamber 42. Therefore, the pressure unevenness on the suction side of the fans 44a (air blowers) of the three FFUs 44 in the FFU installation room 42 becomes smaller. Accordingly, the supply amount of nitrogen from each fan 44a to the transfer chamber 41 becomes stable, and nitrogen easily flows vertically in the transfer chamber 41 (nitrogen forms a laminar flow), making it less likely to raise dust.

In addition, the discharge pipe 49 is connected to the storage chamber 60 of each loading port 4, and the gas discharge to the outside of the circulation path 40 is performed through the plurality of discharge pipes 49 and the plurality of storage chambers 60. Therefore, compared with the case where only one discharge pipe 49 is provided, the gas flowing downward in the transfer chamber 41 can be discharged evenly. This reduces the influence on the laminar flow of nitrogen in the transfer chamber 41 . In addition, the laminar flow of nitrogen in the transfer chamber 41 may be formed at least in the transfer range 200 of the wafer W and above.

In addition, in the transfer chamber 41, the control unit storage box 81 and the measurement device storage box 82 (installation objects) are arranged below the transfer range 200, and the opening 28a is provided in a position not connected with the base portion 90 when viewed from the vertical direction. It can also be used at any overlapping position of the installation.

However, the inventor of the present application conducted laminar flow visualization experiments at three locations above the transport robot arm 3, above the control unit storage box 81, and above the measurement machine storage box 82 (refer to points 201 and 202 in Figure 3 , 203), measure the air flow velocity and confirm the formation state of laminar flow. In this embodiment, the air flow velocity in the conveyance range is 0.3m/s and the rotation number of each FFU is determined in advance. As a result, it was confirmed that the gas passed through collided with the transport robot arm 3 and the like, and no backflow of gas was caused in the transport range 200 . In addition, even if the supply amount of nitrogen from the supply source 111 (see FIG. 3 ) or the rotational speed of the fan 46 (see FIG. 5 ) is changed, it is confirmed that the gas flow rate difference between the above three places is less than 30 %By. That is, even if the installation object is installed in the conveyance range 200, it is confirmed that a stable laminar flow is formed in at least the conveyance range 200 and above.

In addition, the supply port 47a is configured to supply nitrogen toward the range 37b that is closest to the supply port 47a of the support plate 37. Through this, the nitrogen supplied from the supply port 47a first contacts the range 37b of the support plate 37, and flows along the support plate 37 while weakening. Therefore, the airflow flowing in the FFU installation chamber 42 of the FFU 44 from the delivery ports 27f to 27h is less likely to be disrupted, and the pressure unevenness on the suction side of the FFU 44 in the FFU installation chamber 42 becomes smaller. Accordingly, uneven supply of nitrogen from the fan 44a of each FFU 44 to the transfer chamber 41 is suppressed.

As a modified example, the supply port 47a may be configured to supply nitrogen toward the partition wall 32 at the top of the frame 2 or the partition wall 34 at the rear end. Here, similarly to the above, the gas momentum of the nitrogen supplied from the supply port 47a becomes weak and flows, and unevenness in the supply amount of nitrogen from the fan 44a of each FFU 44 to the transfer chamber 41 is further suppressed.

The return path 43 has a space 27a (second flow path) connected to the four spaces 21a to 24a (first flow path), and is formed with delivery ports 27f to 27h in the connecting pipe 27 having the space 27a. The gas in the transfer chamber 41 passes through the four spaces 21a to 24a, temporarily flows into the space 27a, and then flows into the FFU installation chamber 42. In more detail, as shown in Figure 6, the air from space 21a passes through space 27a and heads to the outlet 27f, the air from space 22a passes through space 27a and heads to the left and right outlet 27f, 27g, and the air from space 23a Then, it passes through the space 27a and flows toward the left and right delivery ports 27g and 27h. The air from the space 24a flows through the space 27a and heads toward the delivery port 27h. In this way, the gas from the four spaces 21a to 24a temporarily flows into the space 27a, so that the gas flow rate between the four spaces 21a to 24a can be absorbed unevenly. In this embodiment, the opening areas of the spaces 21a and 24a are larger than those of the spaces 22a and 23a, and the gas circulation amounts in the spaces 21a and 24a are increased. However, the gases from the spaces 21a to 24a are combined in the space 27a, and the gases from the respective spaces 21a to 24a are combined. The delivery ports 27f to 27h deliver the material to the FFU installation room 42. Therefore, compared with the case where the gas is directly sent from the spaces 21a to 24a to the FFU installation chamber 42, the delivery amount of the gas from the delivery ports 27f to 27h is stable, and the pressure unevenness on the suction side of each fan 44a is suppressed, and the pressure from each fan 44a is also suppressed. The supply amount of nitrogen from the fan 44a to the transfer chamber 41 is uneven.

Since the delivery ports 27f to 27h are arranged in the left-right direction between the two adjacent spaces 21a to 24a, even if there is uneven flow of gas from the two adjacent spaces 21a to 24a, the delivery ports will The amount of gas delivered from 27f to 27h is more stable. Therefore, the uneven supply amount of nitrogen from the fan 44a to the transfer chamber 41 is further suppressed.

In addition, each of the delivery ports 27f to 27h is disposed in a position sandwiching the fan 44a between the supply port 47a and the front-rear direction. Thereby, the air flow in the FFU installation chamber 42 flowing from the return path 43 to the fan 44a is less likely to be disrupted, and uneven supply of nitrogen from the fans 44a to the transfer chamber 41 is further suppressed.

The best embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope described in the patent application. In the aforementioned embodiment, the three supply ports 47a formed in the supply pipe 47 are dispersedly arranged in the FFU installation chamber 42. However, in the supply pipe 47, two or more supply ports 47a are arranged in the FFU installation chamber 42. , it can also be configured in a distributed manner. In addition, instead of the supply pipe 47, a porous pipe (for example, porous stone, etc.) may be disposed in the FFU installation chamber 42. Here, a plurality of supply ports of the porous tubes may be dispersedly arranged in the FFU installation chamber 42, and the same effect as that of the above-mentioned embodiment can be obtained.

In addition, a plurality of supply ports 47a may be arranged in each FFU installation chamber 42. That is, it may be disposed on the front end side of the frame 2 . In addition, the opening 28a serving as the gas suction port may be arranged above the lower part of the transfer chamber 41. In addition, the return path 43 is composed only of the spaces 21a to 24a as the first flow path, and the gas may be directly sent from the spaces 21a to 24a to the FFU installation chamber 42. In this case, the number of spaces used as the first flow path may be 1 to 3 or 5 or more. In addition, the return path 43 may have 2, 3, or 5 or more spaces as the second flow path.

In addition, each of the delivery ports 27f to 27h may not be arranged between the two adjacent spaces 21a to 24a in the left-right direction. The number of fans 44a (FFU44) may be 2 or 4 or more. In this case, the communication port 37a may be formed in the support plate 37 corresponding to the fan 44a.

In addition, instead of the delivery ports 27f to 27h, for example, a perforated metal plate (not shown) formed with a plurality of holes may be provided on the entire upper surface of the connecting pipe 27 to change the flow of the gas.

In addition, the spaces 21a to 24a and 27a formed inside the columns 21 to 24 and the connecting pipe 27 serve as the return path 43, but the structure is not limited thereto. That is, the return path 43 may be formed through other members.

1:EFEM 2: Frame 3: Transport robot arm (substrate transport device) 4: Loading port 21a~24a: Space (1st flow path) 27a: Space (2nd flow path) 27f~27h: Send to the exit 28a: Opening (gas suction port) 33: Next door 33a1: Open your mouth 37: Support board 37a: Connecting port 37b: Range 41: Transport room 42: FFU installation room (upper space) 43: Return path (gas return path) 44a: Fan (air blower) 47: Supply pipe (inactive gas supply means) 47a: Supply port 49: Discharge pipe (gas discharge means) W: Wafer (substrate)

FIG. 1 is a plan view showing the schematic configuration of the EFEM and its surroundings according to the first embodiment of the present invention. FIG. 2 is a diagram showing the electrical structure of the EFEM shown in FIG. 1 . Figure 3 is a front view of the frame shown in Figure 1 from the front. FIG. 4 is a cross-sectional view along line IV-IV shown in FIG. 3 . FIG. 5 is a cross-sectional view along line V-V shown in FIG. 3 . FIG. 6 is a cross-sectional view along line VI-VI shown in FIG. 3 . Figure 7 is a side cross-sectional view of the loading port showing the state of the door being closed. Figure 8 is a side cross-sectional view of the loading port showing the state of the door being opened.

2: Frame 21a: Space (1st flow path) 22a: Space (1st flow path) 23a: Space (1st flow path) 24a: Space (1st flow path) 27: Connecting tube 27a: Space (2nd flow path) 27b: Connecting port 27c: Connecting port 27d: Connecting port 27e: Connecting port 27f: Send to the exit 27g: sent to export 27h: Send to the exit 37: Support board 37a: Connecting port 42: FFU installation room (upper space) 44：FFU 45: Chemical filter 47: Supply pipe (inactive gas supply means) 47a: Supply port 48: External piping

Claims (6)

An EFEM characterized by having a frame in which a transfer chamber for transferring substrates is built in and locked by openings provided in the partition walls, connected to the loading port, and and a substrate transfer device disposed in the transfer chamber to transfer the substrate, and are installed in the aforementioned frame, and are provided with a partition member above the aforementioned transfer chamber in order to form an upper space, and inert gas supply means for supplying inert gas to the aforementioned upper space, and a communication port formed in the aforementioned partition member to communicate the aforementioned transfer chamber and the aforementioned upper space, and an air blower arranged to cover the communication port in order to transmit the inert gas in the upper space to the transfer chamber through the communication port. and a gas suction port provided at the lower part of the aforementioned transfer chamber to suck inert gas in the aforementioned transfer chamber, and a gas return path for returning the inert gas sucked from the gas suction port to the upper space, and gas exhaust means for exhausting the gas in the aforementioned transfer chamber; The inert gas supply means includes a supply pipe arranged in the upper space along the length direction of the frame when viewed in a plan view, and the supply pipe has a plurality of supply ports for supplying the inert gas. An EFEM characterized by having a frame in which a transfer chamber for transferring substrates is built in and locked by openings provided in the partition walls, connected to the loading port, and and a substrate transfer device disposed in the transfer chamber to transfer the substrate, and are installed in the aforementioned frame, and are provided with a partition member above the aforementioned transfer chamber in order to form an upper space, and inert gas supply means for supplying inert gas to the aforementioned upper space, and a communication port formed in the aforementioned partition member to communicate the aforementioned transfer chamber and the aforementioned upper space, and an air blower arranged to cover the communication port in order to transmit the inert gas in the upper space to the transfer chamber through the communication port. and a gas suction port provided at the lower part of the aforementioned transfer chamber to suck inert gas in the aforementioned transfer chamber, and a gas return path for returning the inert gas sucked from the gas suction port to the upper space, and gas exhaust means for exhausting the gas in the aforementioned transfer chamber; The inert gas supply means has a plurality of supply ports for supplying the inert gas, which are dispersedly arranged in the upper space, avoiding the upper portion of the connection portion between the return path and the upper space. The EFEM according to Claim 2, wherein the plurality of supply ports include supply pipes arranged along the length direction of the frame when viewed in a plane, The supply pipe system is connected to a partition wall in the short side direction of the frame when viewed in a plane. Such as the EFEM described in any one of claims 1 to 3, wherein the plurality of supply ports supply inert gas from upstream of the air blower. Such as the EFEM described in any one of claims 1 to 3, wherein the plurality of supply ports are arranged so as to avoid the upper part of the air blower. In the EFEM described in claim 4, the plurality of supply ports are arranged so as to avoid the upper part of the air blower.

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