JP7417023B2 - EFEM - Google Patents

Description

The present invention relates to an EFEM (Equipment Front End Module) capable of supplying an inert gas to a closed transfer chamber and replacing the atmosphere with an inert gas atmosphere.

Patent Document 1 describes a load port on which a FOUP (Front-Opening Unified Pod) that accommodates a wafer (semiconductor substrate) is placed, and a load port that is closed by being connected to an opening provided in a front wall. describes an EFEM that includes a housing in which a transfer chamber is formed in which wafers are transferred, and that transfers wafers between a processing device that performs predetermined processing on the wafers and a FOUP.

Conventionally, the effects of oxygen, moisture, etc. in a transfer chamber on semiconductor circuits manufactured on wafers have been small, but in recent years, with the further miniaturization of semiconductor circuits, these effects have become more apparent. Therefore, the EFEM described in Patent Document 1 is configured so that the inside of the transfer chamber is filled with nitrogen, which is an inert gas. Specifically, the EFEM includes a circulation flow path composed of a transfer chamber and a gas return path for circulating nitrogen inside the casing, and a gas supply means for supplying nitrogen to the space above the gas return path. , a plurality of fans arranged in the upper space of the gas return passage to send inert gas to the transfer chamber, and a gas exhaust means for exhausting nitrogen from the lower part of the gas return passage. Nitrogen is supplied and discharged as appropriate depending on changes in oxygen concentration within the circulation channel. This makes it possible to maintain a nitrogen atmosphere inside the transfer chamber.

Japanese Patent Application Publication No. 2015-146349

However, in the EFEM described in 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. The pressure on the suction side of the fan varies from fan to fan, resulting in variation in the amount of supply from each fan to the transfer chamber. In other words, when inert gas is supplied from one side in the arrangement direction of multiple fans, a sufficient amount of inert gas is supplied to one fan, but the amount of inert gas supplied to the other fan is is smaller than the other. That is, the pressure on the suction side of one fan in the upper space becomes greater than that of the other fan, and variations occur in the amount of inert gas supplied from each fan to the transfer chamber. As a result, turbulence occurs in the airflow of the inert gas in the transfer chamber, causing a problem in that dust tends to fly up.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an EFEM that allows inert gas to flow vertically into a transfer chamber and makes it difficult for dust to fly up.

The EFEM of the present invention includes a casing that is closed by connecting a load port to an opening provided in a partition wall and that configures a transfer chamber inside for transferring a substrate; a partition member provided in the housing for forming an upper space above the transfer chamber; and an inert gas supply means for supplying inert gas to the upper space. a plurality of communication ports formed in the partition member and communicating the transfer chamber and the upper space; and a plurality of communication ports arranged to cover each of the communication ports, and inert gas in the upper space through the communication ports. a plurality of blowers for sending gas to the transfer chamber; a gas suction port provided at the bottom of the transfer chamber for sucking inert gas in the transfer chamber; and a gas suction port for sucking inert gas from the gas suction port. The apparatus includes a gas return path for returning gas to the upper space, and a gas discharge means for discharging gas within the transfer chamber. The inert gas supply means has a plurality of supply ports distributed in the upper space for supplying inert gas.

According to this, the inert gas supplied from the inert gas supply means to the upper space can be distributed and supplied from the plurality of supply ports. Therefore, it becomes possible to supply the inert gas evenly throughout the upper space, and the variation in the pressure on the suction side of the plurality of air blowers in the upper space is reduced. Therefore, variations in the amount of inert gas supplied from each blower to the transfer chamber are less likely to occur. As a result, it becomes easier to flow the inert gas vertically within the transfer chamber, making it difficult for dust to fly up.

In the present invention, the supply port is arranged such that the inert gas is directed toward a region closest to the supply port in either the partition wall of the casing or the partition member for partitioning the upper space and the external space. Preferably, it is configured to be supplied. As a result, the inert gas supplied from the supply port hits either the partition member or the partition wall, the force of which is weakened, and the inert gas flows along either the partition member or the partition wall. Therefore, the airflow in the upper space flowing from the gas return path to the blower becomes less likely to be disturbed, and the variation in pressure on the suction side of the plurality of blowers in the upper space becomes smaller. Therefore, variations in the amount of inert gas supplied from each blower to the transfer chamber are further suppressed.

Further, in the present invention, a plurality of the gas suction ports are provided in a lower part of the transfer chamber, and the gas return path includes a plurality of first gas suction ports extending upward from each of the plurality of gas suction ports. It has a flow path and a second flow path connected to the plurality of first flow paths, and further has an outlet for sending gas in the second flow path to the upper space. is preferred. Thereby, the gas from the transfer chamber once flows into the second flow path via the plurality of first flow paths, and then flows into the upper space. By once causing the gas from the plurality of first flow paths to flow into the second flow path in this way, it becomes possible to absorb variations in the amount of gas flowing between the plurality of first flow paths. Therefore, the amount of gas sent from the outlet is more stable than when gas is directly sent to the upper space from each first flow path, and the amount of inert gas supplied from each blower to the transfer chamber is reduced. Variations are further suppressed.

Further, in the present invention, the second flow path extends along the arrangement direction of the plurality of first flow paths, and the outlet port is arranged between the two adjacent first flow paths in the arrangement direction. It is preferable that they are respectively arranged between the roads. Thereby, the amount of gas sent from the outlet to the upper space becomes more stable, and variations in the amount of inert gas supplied from each blower to the transfer chamber are further suppressed.

Further, in the present invention, it is preferable that the air outlet is disposed at a position sandwiching the air blower between the air blower and the supply opening in a cross direction that intersects with the arrangement direction of the plurality of air blowers. As a result, the airflow in the upper space flowing from the gas return path to the blower becomes less likely to be disturbed, and variations in the amount of inert gas supplied from each blower to the transfer chamber are further suppressed.

In addition, from another aspect, the EFEM of the present invention includes a casing that is closed by connecting a load port to an opening provided in a partition wall and that configures a transport chamber inside for transporting a substrate; a partition member provided inside the body to configure an upper space above the transfer chamber; a plurality of communication ports formed in the partition member for communicating the transfer chamber and the upper space; and a plurality of communication ports provided in the communication port. a plurality of blowers provided in the upper space for sending gas from the upper space to the transfer chamber; a plurality of gas suction ports provided at a lower part of the transfer chamber for sucking gas in the transfer chamber; and the gas suction port. and a gas return path for returning gas sucked from each to the upper space. The gas return path is connected to a plurality of first flow paths extending from each of the plurality of gas suction ports and to the plurality of first flow paths so that the gas flows in from the first flow path. and a second flow path for delivering the gas to the upper space.

According to this, the gas from the transfer chamber once flows into the second flow path via the plurality of first flow paths, and then flows into the upper space. By once causing the gas from the plurality of first flow paths to flow into the second flow path in this way, it becomes possible to absorb variations in the gas flow rate among the plurality of first flow paths. For this reason, the amount of gas sent from the outlet is more stable than when gas is sent directly to the upper space from each first flow path, and variations in the amount of gas supplied from each blower to the transfer chamber are reduced. suppressed.

Further, in the present invention, the second flow path extends in a direction crossing the extending direction of the first flow path, and the gas flowing through the gas return path is transferred from the first flow path. Preferably, the direction of the airflow is changed when flowing through the second flow path, and the direction of the airflow is also changed when flowing into the upper space from the second flow path. Thereby, in the second flow path, the flow of gas in the extending direction of the first flow path can be made gentle. Therefore, the airflow in the upper space can be made less turbulent than when the gas flows directly into the upper space without changing the direction of the airflow from the first flow path to the upper space.

Further, in the present invention, the substrate transport device includes a base part whose position is fixed, and a transport part arranged above the base part and transports the substrate, and which is arranged in the transport chamber. The transfer chamber further includes an installation item located below a transfer area where substrates are transferred by the transfer section, and the gas suction port is located between the base section and the transfer chamber when viewed from the vertical direction. It may be arranged at a position that does not overlap with any of the installation objects.

According to the EFEM of the present invention, it becomes possible to supply inert gas evenly throughout the upper space, and variations in pressure on the suction side of the plurality of blowers in the upper space are reduced. Therefore, variations in the amount of inert gas supplied from each blower to the transfer chamber are less likely to occur. As a result, it becomes easier to flow the inert gas vertically within the transfer chamber, making it difficult for dust to fly up.

1 is a plan view showing a schematic configuration of an EFEM and its surroundings according to an embodiment of the present invention. 2 is a diagram showing the electrical configuration of the EFEM shown in FIG. 1. FIG. FIG. 2 is a front view of the casing shown in FIG. 1 when viewed from the front. 4 is a cross-sectional view taken along the line IV-IV shown in FIG. 3. FIG. 4 is a cross-sectional view taken along the line VV shown in FIG. 3. FIG. 4 is a cross-sectional view taken along line VI-VI shown in FIG. 3. FIG. FIG. 3 is a side cross-sectional view of the load port showing a state in which the door is closed. FIG. 3 is a side sectional view of the load port showing the door in an open state.

An EFEM 1 according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 8. For convenience of explanation, the directions shown in FIG. 1 are referred to as 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 defined as the front-rear direction, with the EFEM 1 side being the front and the substrate processing apparatus 6 side being the rear. Further, the direction in which the plurality of load ports 4 are arranged, which is orthogonal to the front-rear direction, is defined as the left-right direction. Further, a direction perpendicular to both the front-back direction and the left-right direction is defined as the up-down direction.

(Schematic configuration of EFEM and its surroundings)
First, the schematic configuration of the EFEM 1 and its surroundings will be described using FIGS. 1 and 2. FIG. 1 is a plan view showing a schematic configuration of an EFEM 1 and its surroundings according to the present embodiment. FIG. 2 is a diagram showing the electrical configuration of the EFEM 1. As shown in FIG. 1, the EFEM 1 includes a housing 2, a transfer robot 3 (substrate transfer device), three load ports 4, and a control device 5. A substrate processing device 6 is arranged behind the EFEM 1 to perform predetermined processing on a wafer W (substrate). The EFEM 1 transfers the wafer W between a FOUP (Front-Opening Unified Pod) 100 placed on a load port 4 and a substrate processing apparatus 6 using a transfer robot 3 disposed in a housing 2 . The FOUP 100 is a container that can accommodate a plurality of wafers W arranged in the vertical direction, and is provided with a lid 101 that can be opened and closed at the rear end (the end on the housing 2 side in the front-rear direction). The FOUP 100 is transported by, for example, a known OHT (overhead automatic guided vehicle: not shown). The FOUP 100 is transferred between the OHT and the load port 4.

The casing 2 is for connecting the three load ports 4 and the substrate processing apparatus 6. A transfer chamber 41 is formed inside the casing 2, which is substantially sealed from the outside space and for transferring the wafer W without exposing it to the outside air. When the EFEM 1 is in operation, the transfer chamber 41 is filled with nitrogen. In this embodiment, the transfer chamber 41 is filled with nitrogen, but it may be filled with an inert gas other than nitrogen (for example, argon, etc.). The housing 2 is configured so that nitrogen circulates in the internal space including the transfer chamber 41 (details will be described later). Further, a door 2a that can be opened and closed is provided at the rear end of the housing 2, and the transfer chamber 41 is connected to the substrate processing apparatus 6 across the door 2a.

The transport robot 3 is arranged within the transport chamber 41 and transports the wafer W. The transfer robot 3 includes a base section 90 (see FIG. 3) whose position is fixed, and an arm mechanism 70 (transfer section; see FIG. 3) that is disposed above the base section 90 and holds and transfers the wafer W. and a robot control section 11 (see FIG. 2). The transport robot 3 mainly performs operations such as taking out a wafer W from the FOUP 100 and delivering it to the substrate processing apparatus 6, and receiving a wafer W processed by the substrate processing apparatus 6 and returning it to the FOUP 100.

The load port 4 is for placing the FOUP 100 (see FIG. 7). As shown in FIGS. 1 and 5, the plurality of load ports 4 are arranged side by side in the left-right direction along the partition wall 33 on the front side of the housing 2. Each load port 4 closes three openings 33a1 (see FIG. 4) formed in the partition wall 33 of the housing 2 with a base 51 (see FIG. 7) at the rear end. Thereby, the transfer chamber 41 is configured as a substantially sealed space within the housing 2. Further, the load port 4 is configured to be able to replace the atmosphere inside the FOUP 100 with nitrogen. A door 4a that is part of an opening/closing mechanism 54, which will be described later, is provided at the rear end of the load port 4. The door 4a is opened and closed by a door drive mechanism 55 (a part of the opening/closing mechanism 54). The door 4a is configured to be able to unlock the lid 101 of the FOUP 100 and to hold the lid 101. With the door 4a holding the unlocked lid 101, the door drive mechanism 55 opens the door 4a, thereby opening the lid 101. Thereby, the wafer W in the FOUP 100 can be taken out by the transfer robot 3. Further, the wafer W can be stored in the FOUP 100 by the transfer robot 3.

As shown in FIG. 2, the control device 5 is electrically connected to the robot control section 11 of the transfer robot 3, the load port control section 12 of the load port 4, and the control section (not shown) of the substrate processing apparatus 6. , communicates with these control units. Further, the control device 5 is electrically connected to an oxygen concentration meter 85, a pressure gauge 86, a hygrometer 87, etc. installed in the housing 2, and receives the measurement results of these measuring devices and transmits them to the housing. Information regarding the atmosphere inside the body 2 is grasped. Further, the control device 5 is electrically connected to a supply valve 112 and a discharge valve 113 (described later), and adjusts the nitrogen atmosphere within the casing 2 as appropriate by adjusting the opening degrees of these valves.

As shown in FIG. 1, the substrate processing apparatus 6 includes, for example, a load lock chamber 6a and a processing chamber 6b. The load lock chamber 6a is a room connected to the transfer chamber 41 across the door 2a of the housing 2, and is used to temporarily hold the wafer W. The processing chamber 6b is connected to the load lock chamber 6a across a door 6c. In the processing chamber 6b, a predetermined process is performed on the wafer W by a processing mechanism (not shown).

(Case and its internal configuration)
Next, the casing 2 and its internal configuration will be explained using FIGS. 3 to 6. FIG. 3 is a front view of the housing 2 when viewed from the front. FIG. 4 is a cross-sectional view taken along the line IV-IV shown in FIG. FIG. 5 is a sectional view taken along line VV shown in FIG. 3. FIG. 6 is a cross-sectional view taken along the line VI-VI shown in FIG. Note that in FIGS. 3 and 6, illustration of the partition wall is omitted. Further, in FIG. 5, illustration of the transport robot 3 and the like is omitted, and the load port 4 is shown by a two-dot chain line.

The housing 2 has a generally rectangular parallelepiped shape as a whole. As shown in FIGS. 3 to 5, the housing 2 includes pillars 21 to 26, a connecting pipe 27, and partition walls 31 to 36. Partition walls 31 to 36 are attached to columns 21 to 26 extending in the vertical direction, and the internal space of the housing 2 (transfer chamber 41 and FFU installation chamber 42) is configured to be substantially airtight with respect to the external space.

More specifically, as shown in FIG. 4, at the front end of the housing 2, columns 21 to 24 are arranged in order from left to right while being spaced apart from each other. That is, the four pillars 21 to 24 are arranged along the left-right direction. Further, the pillars 21 to 24 are erected along the vertical direction, as shown in FIG. The pillars 21 and 24 are composed of first portions 21b and 24b arranged on the lower side and second portions 21c and 24c arranged on the upper side. The first portions 21b and 24b are erected on the partition wall 31 and have their upper ends connected to the connecting pipe 27. Further, the pillars 22 and 23 are also erected on the partition wall 31, and their upper ends are connected to the connecting pipe 27. These first portions 21b, 24b and pillars 22, 23 have approximately the same length in the vertical direction. The second portions 21c, 24c are provided upright on the connecting pipe 27 at positions overlapping the first portions 21b, 24b in the vertical direction. Two pillars 25 and 26 are arranged vertically on both left and right sides of the rear end of the housing 2. 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.

As shown in FIG. 3, a partition 31 is arranged at the bottom of the housing 2, and a partition 32 is arranged at the ceiling. As shown in FIG. 4, a partition 33 is disposed at the front end, a partition 34 at the rear end, a partition 35 at the left end, and a partition 36 at the right end. The partition wall 33 is formed with the three openings 33a1 described above. These three openings 33a1 are arranged between the four pillars 21 to 24 in the left-right direction, and are closed by the base 51 of the load port 4. A mounting section 83 (see FIG. 3) on which an aligner 84 (described later) is mounted is provided at the right end of the housing 2. The aligner 84 and the mounting section 83 are also housed inside the housing 2 (see FIG. 4).

As shown in FIG. 5, a support plate 37 (partition member) extending in the horizontal direction is disposed in the upper part of the housing 2 at the rear end side of the connecting pipe 27. As shown in FIG. As a result, the inside of the casing 2 is divided into the aforementioned transfer chamber 41 and an FFU installation chamber 42 formed above the transfer chamber 41. In other words, the support plate 37 forms an FFU installation chamber 42 as an upper space above the transfer chamber 41 in the internal space of the casing 2 .

In the FFU installation chamber 42, three FFUs (fan filter units) 44, which will be described later, are arranged. Three communication ports 37a are formed at a central portion of the support plate 37 in the front-rear direction and at a position facing the FFU 44 in the vertical direction, allowing the transfer chamber 41 and the FFU installation chamber 42 to communicate with each other. These three communication ports 37a are arranged side by side along the left-right direction, as shown in FIG. Further, the three communication ports 37a are arranged between the four pillars 21 to 24 in the left-right direction. The partition walls 33 to 36 of the casing 2 are divided into a lower wall for the transfer chamber 41 and an upper wall for the FFU installation chamber 42 (for example, the partition walls 33a and 33b at the front end and the rear wall in FIG. ). The rotational speed of each FFU 44 is determined in advance so that the airflow velocity in the transport area 200, which will be described later, becomes a desired value. The airflow velocity in the conveying area 200 is less than 1 m/s, preferably 0.1 m/s to 0.7 m/s, more preferably 0.2 m/s to 0.6 m/s, and the target The rotation speed of each FFU is determined according to the value of .

Next, the internal configuration of the housing 2 will be explained. Specifically, the configuration for circulating nitrogen within the casing 2, the peripheral configuration thereof, the equipment arranged within the transfer chamber 41, etc. will be described.

The configuration for circulating nitrogen within the casing 2 and its peripheral configuration will be explained using FIGS. 3 to 6. As shown in FIG. 5, a circulation path 40 for circulating nitrogen is formed inside the housing 2. The circulation path 40 includes a transfer chamber 41, an FFU installation chamber 42, and a 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 37 a and reaches the lower end of the transfer chamber 41 , then rises through the return path 43 and flows into the FFU installation chamber 42 . (See the arrow in Figure 5). This will be explained in detail below.

The FFU installation chamber 42 is provided with three FFUs 44 placed on the support plate 37 and three chemical filters 45 placed on the FFUs 44, as shown in FIGS. 5 and 6. 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 so as to cover the communication port 37a. As shown by the arrow in FIG. 6, the FFU 44 uses a fan 44a to suck in nitrogen in the FFU installation chamber 42 from around the FFU 44 and sends it downward, while removing particles (not shown) contained in the nitrogen using a filter 44b. . The chemical filter 45 is for removing active gas etc. brought into the circulation path 40 from the substrate processing apparatus 6, for example. 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 a communication port 37a formed in the support plate 37. The nitrogen sent into the transfer chamber 41 forms a laminar flow and flows downward.

The return path 43 is formed in the pillars 21 to 24 (post 23 in FIG. 5) arranged at the front end of the housing 2 and the connecting pipe 27. The first portions 21b, 24b of the pillars 21, 24, the pillars 22, 23, and the connecting pipe 27 are hollow, and spaces 21a to 24a, 27a are formed in which nitrogen can flow to each other ( (See Figure 4). The first portions 21b, 24b of the columns 21, 24 have a width larger in the left-right direction than the columns 22, 23, as shown in FIG. In other words, the planar size of the spaces 21a, 24a (first flow path) (i.e., the first portion 21b,
24b (opening area) is larger than spaces 22a, 23a (opening area of pillars 22, 23). Further, the spaces 21a to 24a (first flow paths) are formed to extend in the vertical direction, and all 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 housing 2 . The space 27a (second flow path) of the connecting pipe 27 extends in the left-right direction. Furthermore, as shown in FIGS. 5 and 6, communication ports 27b to 27e are formed in the lower surface of the connecting pipe 27 to allow the spaces 21a to 24a and the space 27a to communicate with each other. Furthermore, as shown in FIG. 6, three outlet ports 27f to 27h are formed on the upper surface of the connecting pipe 27 and open toward the FFU installation chamber 42 (that is, toward the top). These three outlet ports 27f to 27h are arranged between the four pillars 21 to 24 in the left-right direction, and each have a rectangular planar shape that is elongated in the left-right direction. Further, the three outlet ports 27f to 27h are arranged at the front end of the housing 2. In this way, the connecting pipe 27 is configured to be able to once combine the nitrogen flowing in from the four spaces 21a to 24a and then send it out to the FFU installation chamber 42 from the three outlets 27f to 27h. When nitrogen flows from spaces 21a to 24a to space 27a, the direction of the airflow is changed from above to the left and right, and when nitrogen flows from space 27a to FFU installation chamber 42 via outlet ports 27f to 27h, The direction of the airflow is changed from left and right to upward. A return path 43 is constituted by such spaces 21a to 24a and 27a. Furthermore, the three outlet ports 27f to 27h are arranged at positions overlapping the FFU 44 along the front-rear direction. In other words, the outlet ports 27f to 27h and the FFU 44 which are adjacent in the front-rear direction correspond to each other. The three outlet ports 27f to 27h are elongated in the left-right direction and have a relatively large opening area. Therefore, the flow of gas sent to the FFU installation chamber 42 from each of the delivery ports 27f to 27h becomes gentle, and variations in pressure on the suction side (upper side) of the three FFUs 44 are reduced. Note that the gas delivered to the FFU installation chamber 42 from the delivery ports 27f to 27h flows upward through between the partition wall 33 and the FFU 44, as shown in FIG.

The return path 43 will be explained in more detail with reference to FIG. 5. Although the pillar 23 is shown in FIG. 5, the same applies to the first portions 21b and 24b of the other pillars 21 and 24 and the pillar 22. An introduction duct 28 is attached to 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 attached to the other pillars 21, 22, and 24. Note that since the pillars 21 and 24 are formed wider than the pillar 23 in the left-right direction, the introduction duct 28 to which they are attached is also formed wider, but other than this, they have the same configuration. An opening 28 a is formed in the introduction duct 28 so that nitrogen that has reached the lower end of the transfer chamber 41 can flow into the return path 43 . In other words, the opening 28a is a gas suction port that sucks nitrogen in the transfer chamber 41 into the return path 43. Further, the opening 28a is configured to face downward. Therefore, the gas that has reached the partition wall 31 from above can be smoothly sucked in without disturbing the flow of gas from above. Furthermore, the gas sucked in through the opening 28a can flow upward without changing the airflow direction.

An enlarged portion 28b is formed in the upper part of the introduction duct 28 and expands toward the rear as it goes downward. A fan 46 is arranged within the introduction duct 28 and below the enlarged portion 28b. The fan 46 is driven by a motor (not shown), sucks nitrogen that has reached 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 chamber 42. The nitrogen returned to the FFU installation chamber 42 is sucked into the FFU 44 side from the upper surface of the chemical filter 45, purified by the FFU 44 and the chemical filter 45, and sent out to the transfer chamber 41 via the communication port 37a again. As described above, nitrogen can be circulated within the circulation path 40.

Further, as shown in FIG. 3, the upper rear end of the FFU installation chamber 42 (that is, the rear end of the housing 2)
A supply pipe 47 for supplying nitrogen into the FFU installation chamber 42 (circulation path 40) is arranged. The supply pipe 47 is connected to an external pipe 48 that is connected to a nitrogen supply source 111. A supply valve 112 that can change the amount of nitrogen supplied per unit time is provided in the middle of the external piping 48 . These supply pipe 47, external pipe 48, supply valve 112, and supply source 111 constitute an inert gas supply means. Note that if an 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 consist only of the supply pipe 47.

As shown in FIGS. 3 and 6, the supply pipe 47 extends in the left-right direction, and has three supply ports 47a formed therein. The three supply ports 47a are spaced apart from each other along the left-right direction, and supply nitrogen into the FFU installation chamber 42 from the supply pipe 47. These three supply ports 47a are formed at the lower end of the supply pipe 47, as shown in FIGS. The structure is such that nitrogen is supplied toward the region (the region closest to the supply port 47a). Further, the three supply ports 47a are arranged in the same positional relationship as the center of the FFU 44 in the left-right direction. Thereby, the three supply ports 47a are arranged at positions sandwiching the fan 44a between the outlet ports 27f to 27h in the front-rear direction.

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 distributed in the FFU installation chamber 42, the nitrogen is supplied to the FFU installation chamber 42. It is evenly supplied to the entire chamber 42. For example, when nitrogen is directly supplied into the FFU installation chamber 42 from one supply port of the external piping 48 connected to the right end of the housing 2, the pressure in the right side of the FFU installation chamber 42 increases. . That is, the pressure on the suction side of the rightmost FFU 44 is higher than that of the other two FFUs 44 . If large variations occur in the pressure on the suction side of the FFUs 44 in this way, variations will likely occur in the amount of nitrogen supplied from the three FFUs 44 to the transfer chamber 41. However, in this embodiment, since nitrogen is supplied from the three supply ports 47a that are spaced apart from each other in the left-right direction, the variation in pressure on the suction side of the three FFUs 44 is reduced. Therefore, the amount of nitrogen supplied from the three FFUs 44 to the transfer chamber 41 is stabilized, and the nitrogen sent to the transfer chamber 41 forms a laminar flow and flows downward.

Further, as shown in FIG. 5, a discharge pipe 49 for discharging the gas in the circulation path 40 is connected to the lower end of the load port 4. Note that the load port 4 communicates with a storage chamber 60 in which a door drive mechanism 55 is accommodated via a slit 51b formed in the base 51 (see FIG. 7), as will be described later. A discharge pipe 49 is connected to the storage chamber 60. The exhaust pipe 49 is connected to, for example, an exhaust port (not shown), and an exhaust valve 113 that can change the amount of gas discharged from the circulation path 40 per unit time is provided at an intermediate location. These exhaust pipe 49 and exhaust valve 113 constitute a gas exhaust means.

The supply valve 112 and the discharge valve 113 are electrically connected to the control device 5 (see FIG. 2). This makes it possible to supply and discharge nitrogen to and from the circulation path 40 as appropriate. For example, when starting the EFEM 1 (for example, including when starting the EFME 1 after maintenance), if the oxygen concentration in the circulation path 40 is rising, the By supplying nitrogen to the circulation path 40 and discharging the gas (gas: containing nitrogen, oxygen, etc.) in the circulation path 40 and the storage chamber 60 via the discharge pipe 49, the oxygen concentration can be lowered. In other words, the inside of the circulation path 40 and the storage chamber 60 can be replaced with a nitrogen atmosphere. Note that even if the oxygen concentration in the circulation path 40 increases while the EFEM 1 is in operation, it is possible to temporarily supply more nitrogen to the circulation path 40 and exhaust oxygen together with nitrogen through the exhaust pipe 49. This can lower the oxygen concentration. For example, in the EFEM 1 of the type that circulates nitrogen, in order to suppress the leakage of nitrogen from the circulation path 40 to the outside and to reliably suppress the intrusion of the atmosphere from the outside into the circulation path 40, the inside of the circulation path 40 is It is necessary to keep the pressure slightly higher than the external pressure. Specifically, it is within the range of 1 Pa (G) to 3000 Pa (G), preferably 3 Pa (G) to 500 Pa (G), and more preferably 5 Pa (G) to 100 Pa (G). Therefore, when the pressure in the circulation path 40 deviates from a predetermined range, the control device 5 changes the nitrogen discharge flow rate by changing the opening degree of the discharge valve 113 so that the pressure reaches a predetermined target pressure. Adjust to In this way, the oxygen concentration and pressure are controlled by adjusting the nitrogen supply flow rate based on the oxygen concentration and adjusting the nitrogen discharge flow rate based on the 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 explained using FIGS. 3 and 4. As shown in FIGS. 3 and 4, in the transfer chamber 41, the above-mentioned transfer robot 3, a control unit storage box 81, a measuring device storage box 82, and an aligner 84 are arranged. The control unit storage box 81 is installed, for example, to the left of the base unit 90 (see FIG. 3) of the transfer robot 3, and is located below the transfer area 200 where the wafer W is transferred by the arm mechanism 70 (see FIG. 3). It is located. The control unit storage box 81 accommodates the robot control unit 11 and load port control unit 12 described above. The measuring device storage box 82 is installed, for example, on the right side of the base section 90 and is located below the transfer area 200 of the arm mechanism 70. The measuring device storage box 82 can accommodate measuring devices (see FIG. 2) such as the oxygen concentration meter 85, pressure gauge 86, and hygrometer 87 described above. The control unit housing box 81 and the measuring equipment housing box 82 correspond to the installed objects of the present invention. The introduction duct 28 (see FIG. 4) described above is arranged in front of the base section 90, the control section housing box 81, and the measuring equipment housing box 82. That is, the opening 28a is arranged at a position that does not overlap with any of the base section 90, the control section housing box 81, and the measuring equipment housing box 82 when viewed from the top and bottom (vertical direction) (see FIG. 4, (See Figure 5).

The aligner 84 is for detecting how far the holding position of the wafer W held by the arm mechanism 70 (see FIG. 3) of the transfer robot 3 deviates from the target holding position. For example, there is a risk that the wafer W may move slightly inside the FOUP 100 (see FIG. 1) that is transported by the above-mentioned OHT (not shown). Therefore, the transfer robot 3 temporarily places the unprocessed wafer W taken out from the FOUP 100 on the aligner 84. The aligner 84 measures how far the wafer W is held by the transfer robot 3 from the target holding position, and transmits the measurement result to the robot control unit 11 . The robot control unit 11 corrects the holding position by the arm mechanism 70 based on the measurement results, controls the arm mechanism 70 to hold the wafer W at the target holding position, and moves the wafer W to the load lock chamber 6a of the substrate processing apparatus 6. Have it transported. Thereby, the processing of the wafer W by the substrate processing apparatus 6 can be performed normally.

(Load port configuration)
Next, the configuration of the load port will be described below with reference to FIGS. 7 and 8. FIG. 7 is a side sectional view of the load port with the door closed. FIG. 8 is a side sectional view of the load port showing the door in an open state. Note that FIGS. 7 and 8 are illustrated with the external cover 4b (see FIG. 5) located below the mounting table 53 removed.

As shown in FIG. 7, the load port 4 includes a plate-shaped base 51 that stands upright along the vertical direction, and a horizontal base 52 that is formed to protrude forward from the vertical center of the base 51. It has A mounting table 53 for mounting the FOUP 100 is provided above the horizontal base 52. With the FOUP 100 placed thereon, the mounting table 53 can be moved in the front-back direction by a mounting table driving section (not shown).

The base 51 constitutes a 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 elongated in the vertical direction when viewed from the front. Also, base 5
1, a window portion 51a is formed at a position that can face the placed FOUP 100 in the front-back direction. Further, the base 51 has a slit 51b extending in the vertical direction at a position lower than the horizontal base 52 in the vertical direction, through which a support frame 56, which will be described later, is movable. The slit 51b is formed only in the range in which the support frame 56 can move up and down while passing through the base 51, and the width of the opening in the left and right direction is small. Therefore, particles in the storage chamber 60 are less likely to enter the transfer chamber 41 through the slit 51b.

The load port 4 has an opening/closing mechanism 54 that can open and close the lid 101 of the FOUP 100. The opening/closing mechanism 54 includes a door 4a that can close the window 51a, and a door drive mechanism 55 that drives the door 4a. The door 4a is configured to be able to close the window portion 51a. Further, the door 4a is configured to be able to unlock the lid 101 of the FOUP 100 and to hold the lid 101. The door drive mechanism 55 includes a support frame 56 for supporting the door 4a, a movable block 58 that supports the support frame 56 so as to be movable in the front-rear direction via a slide support means 57, and a movable block 58 attached to the base 51. It includes a slide rail 59 that is movably supported in the vertical direction.

The support frame 56 supports the rear lower part of the door 4a, and has a substantially crank shape that extends downward, passes through a slit 51b provided in the base 51, and projects toward the front of the base 51. This is a plate-like member. A slide support means 57, a movable block 58, and a slide rail 59 for supporting the support frame 56 are provided in front of the base 51. That is, a driving part for moving the door 4a is located outside the housing 2 and is housed in a housing chamber 60 provided below the horizontal base 52. The storage chamber 60 is surrounded by a horizontal base 52, a substantially box-shaped cover 61 extending downward from the horizontal base 52, and a base 51, and is in a substantially sealed state.

The above-mentioned discharge pipe 49 is connected to the bottom wall 61a of the cover 61. In other words, 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 each other in any of the three load ports 4. Thereby, the gas in the circulation path 40 can be discharged from the discharge pipe 49 via the storage chamber 60. When the gas is discharged from the discharge pipe 49, particles present in the storage chamber 60 can also be discharged together with the gas. Further, a fan 62 facing the discharge pipe 49 is provided inside the storage chamber 60 and on the bottom wall 61a. By providing the fan 62 in the storage chamber 60 in this manner, gas can be easily discharged from the storage chamber 60 to the exhaust pipe 49 while suppressing particles from flying up. If a fan is provided to send the gas in the transfer chamber 41 toward the storage chamber 60, the air flow in the transfer chamber 41 will be easily disturbed, and the particles in the transfer chamber 41 will be likely to be thrown up. In this embodiment, since the fan 62 is disposed within the storage chamber 60, it is possible to suppress particles within the transfer chamber 41 from flying up.

Next, the opening and closing operations of the lid 101 and door 4a of the FOUP 100 will be described below. First, as shown in FIG. 7, the FOUP 100 placed on the mounting table 53 in a state separated from the base 51 is moved backward so that the lid 101 and the door 4a come into contact with each other. . At this time, the door 4a of the opening/closing mechanism 54 unlocks the lid 101 of the FOUP 100 and holds the lid 101.

Next, as shown in FIG. 8, the support frame 56 is moved rearward. This causes the door 4a and the lid 101 to move rearward. By doing this, the lid 101 of the FOUP 100 opens and the door 4a opens, allowing the transfer chamber 41 of the housing 2 and the FOUP 100 to communicate with each other.

Next, as shown in FIG. 8, the support frame 56 is moved downward. This causes the door 4a and the lid 101 to move downward. By doing so, the FOUP 100 is largely opened as a loading/unloading entrance, and the wafer W can be moved between the FOUP 100 and the EFEM 1. In addition, when closing the lid 101 and the door 4a, the operation described above may be reversed. Further, a series of operations of the load port 4 is controlled by a load port control section 12.

As described above, according to the EFEM 1 of this embodiment, the three supply ports 47a are distributed and arranged within the FFU installation chamber 42, so that nitrogen can be evenly supplied throughout the FFU installation chamber 42. becomes possible. Therefore, variations in pressure on the suction side of the fans 44a (air blowers) of the three FFUs 44 in the FFU installation chamber 42 are reduced. Therefore, the amount of nitrogen supplied from each fan 44a to the transfer chamber 41 is stabilized, making it easier to flow nitrogen vertically within the transfer chamber 41 (nitrogen forms a laminar flow), and making it difficult for dust to fly up.

Further, the discharge pipe 49 is connected to the storage chamber 60 of each load port 4, and the gas is discharged to the outside of the circulation path 40 via the plurality of discharge pipes 49 and the plurality of storage chambers 60. Therefore, compared to the case where only one discharge pipe 49 is provided, the gas flowing downward within the transfer chamber 41 can be uniformly discharged. This reduces the influence on the laminar flow formed by nitrogen in the transfer chamber 41. Further, the laminar flow formed by nitrogen in the transfer chamber 41 only needs to be formed at least in the transfer region 200 of the wafer W and above it.

Further, in the transfer chamber 41, a control unit storage box 81 and a measuring device storage box 82 (installed objects) are arranged below the transfer area 200, and the opening 28a is located below the base portion 90 when viewed from the vertical direction. and may be provided at a position that does not overlap with any of the installed objects.

In addition, the inventor of the present application has determined that three locations (points 201, 202, and 203 in FIG. (see), the airflow velocity was measured and the formation of laminar flow was confirmed. In this embodiment, the rotation speed of each FFU was determined in advance so that the airflow velocity in the transport area was 0.3 m/s. As a result, it was confirmed that the backflow of gas to the transfer area 200 due to gas colliding with the transfer robot 3 etc. did not occur. Furthermore, even if the amount of nitrogen supplied from the supply source 111 (see FIG. 3) and the rotation speed of the fan 46 (see FIG. 5) are changed, the difference in gas flow rate between the three locations mentioned above is less than 30%. It was confirmed that In other words, it was confirmed that a stable laminar flow was formed at least in the transport area 200 and above, even if an object was provided in the transport area 200.

Further, the supply port 47a is configured so that nitrogen is supplied toward the region 37b of the support plate 37 that is closest to the supply port 47a. As a result, the nitrogen supplied from the supply port 47a first hits the region 37b of the support plate 37, and its force becomes weak and flows along the support plate 37. Therefore, the airflow in the FFU installation chamber 42 flowing from the outlet ports 27f to 27h to the FFU 44 is less likely to be disturbed, and the variation in pressure on the suction side of the FFU 44 in the FFU installation chamber 42 is reduced. Therefore, variations in the amount of nitrogen supplied from the fan 44a of each FFU 44 to the transfer chamber 41 are further suppressed.

As a modification, the supply port 47a may be configured so that nitrogen is supplied toward the partition wall 32 at the ceiling of the housing 2 or the partition wall 34 at the rear end. In this case as well, as described above, the force of the nitrogen supplied from the supply port 47a becomes weaker and flows, thereby further suppressing variations in the amount of nitrogen supplied from the fan 44a of each FFU 44 to the transfer chamber 41.

The return path 43 has a space 27a (second flow path) connected to four spaces 21a to 24a (first flow path), and outlet ports 27f to 27h are formed in the connecting pipe 27 having the space 27a. As a result, the gas from the transfer chamber 41 first flows to the space 27a via the four spaces 21a to 24a, and then flows to the FFU installation chamber 42. More specifically, as shown in FIG. 6, the gas from the space 21a passes through the space 27a and heads toward the outlet 27f, and the gas from the space 22a passes through the space 27a and heads toward the left and right outlets 27f and 27g. Gas from the space 23a flows through the space 27a toward the left and right outlets 27g and 27h, and gas from the space 24a flows through the space 27a toward the outlet 27h. By once causing the gas from the four spaces 21a to 24a to flow into the space 27a in this way, it becomes possible to absorb variations in the amount of gas flowing between the four spaces 21a to 24a. In this embodiment, the opening areas of the spaces 21a and 24a are larger than those of the spaces 22a and 23a, and the amount of gas flowing through the spaces 21a and 24a is larger. The gases are combined and sent to the FFU installation chamber 42 from each outlet 27f to 27h. Therefore, the amount of gas delivered from the delivery ports 27f to 27h is more stable than when gas is delivered directly from each space 21a to 24a to the FFU installation chamber 42, and the pressure on the suction side of each fan 44a varies. This also suppresses variations in the amount of nitrogen supplied from each fan 44a to the transfer chamber 41.

Each of the outlets 27f to 27h is arranged between two adjacent spaces 21a to 24a in the left-right direction, so even if there is variation in the amount of gas flowing from the two adjacent spaces 21a to 24a, The amount of gas delivered from the delivery ports 27f to 27h becomes more stable. Therefore, variations in the amount of nitrogen supplied from the fan 44a to the transfer chamber 41 are further suppressed.

Further, each of the outlet ports 27f to 27h is arranged at a position sandwiching the fan 44a between the outlet port 47a and the supply port 47a in the front-rear direction. As a result, the airflow in the FFU installation chamber 42 flowing from the return path 43 to the fan 44a becomes less likely to be disturbed, and variations in the amount of nitrogen supplied from each fan 44a to the transfer chamber 41 are further suppressed.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. In the above-described embodiment, the three supply ports 47a formed in the supply pipe 47 were arranged in a dispersed manner in the FFU installation chamber 42, but two or four or more supply ports 47a formed in the supply pipe 47 were arranged in the FFU installation chamber 42. In the chamber 42, they may be arranged in a dispersed manner. Further, instead of the supply pipe 47, a porous pipe (eg, air stone, etc.) may be arranged in the FFU installation chamber 42. Also in this case, the plurality of supply ports of the porous tubes are arranged in a distributed manner in the FFU installation chamber 42, and the same effects as in the above-described embodiment can be obtained.

Further, the plurality of supply ports 47a may be placed anywhere in the FFU installation chamber 42. That is, it may be arranged on the front end side of the housing 2. Further, the opening 28a serving as the gas suction port may be arranged above the lower part of the transfer chamber 41. Further, the return path 43 may be composed of only the spaces 21a to 24a as the first flow paths, and the gas may be sent directly to the FFU installation chamber 42 from each of the spaces 21a to 24a. In this case, the number of spaces serving as the first flow path may be 1 to 3 or 5 or more. Moreover, when the return path 43 has the space 27a as a second flow path, the number of spaces as the first flow path may be 2, 3, or 5 or more.

Further, each of the outlet ports 27f to 27h may not be arranged between two adjacent spaces 21a to 24a in the left-right direction. Two or four or more fans 44a (FFU44) may be provided. In this case, the communication port 37a may also be formed in the support plate 37 in correspondence with the fan 44a.

Further, instead of the outlet ports 27f to 27h, for example, a punching metal (not shown) in which a large number of holes are formed may be provided over the entire upper surface of the connecting pipe 27 to change the flow of gas.

Furthermore, although the spaces 21a to 24a and 27a formed inside the pillars 21 to 24 and the connecting pipe 27 are the return path 43, the present invention is not limited to this. That is, the return path 43 may be formed of other members.

1 EFEM
2 Housing 3 Transfer robot (substrate transfer device)
4 Load ports 21a to 24a space (first flow path)
27a Space (second flow path)
27f to 27h Outlet port 28a Opening (gas suction port)
33 Partition wall 33a1 Opening 37 Support plate 37a Communication port 37b Region 41 Transfer chamber 42 FFU installation chamber (upper space)
43 Return path (gas return path)
44a Fan (Blower)
47 Supply pipe (inert gas supply means)
47a Supply port 49 Discharge pipe (gas discharge means)
W wafer (substrate)

Claims (5)

a casing that is closed by connecting a load port to an opening provided in a partition wall, and has a transport chamber therein for transporting the substrate;
a substrate transport device that is disposed within the transport chamber and transports the substrate;
a partition member provided within the casing and configured to form an upper space above the transfer chamber;
Inert gas supply means for supplying inert gas to the upper space;
a communication port formed in the partition member and communicating the transfer chamber and the upper space;
a blower arranged to cover the communication port and for sending inert gas in the upper space to the transfer chamber via the communication port;
a gas suction port provided at a lower part of the transfer chamber for sucking inert gas in the transfer chamber;
a gas return path that returns the inert gas sucked from the gas suction port to the upper space;
and a gas exhaust means for exhausting the gas in the transfer chamber,
The inert gas supply means includes a supply pipe arranged in the upper space along the longitudinal direction of the housing when viewed from above, and the supply pipe has a plurality of pipes for supplying inert gas. An EFEM characterized by having a supply port.
a casing that is closed by connecting a load port to an opening provided in a partition wall, and has a transport chamber therein for transporting the substrate;
a substrate transport device that is disposed within the transport chamber and transports the substrate;
a partition member provided within the casing and configured to form an upper space above the transfer chamber;
Inert gas supply means for supplying inert gas to the upper space;
a communication port formed in the partition member and communicating the transfer chamber and the upper space;
a blower arranged to cover the communication port and for sending inert gas in the upper space to the transfer chamber via the communication port;
a gas suction port provided at a lower part of the transfer chamber for sucking inert gas in the transfer chamber;
a gas return path that returns the inert gas sucked from the gas suction port to the upper space;
and a gas exhaust means for exhausting the gas in the transfer chamber,
The inert gas supply means has a plurality of supply ports for supplying inert gas, which are distributed in the upper space so as to avoid the upper part of the connection between the return path and the upper space. EFEM is characterized by
The plurality of supply ports are provided in a supply pipe arranged along a longitudinal direction when the casing is viewed from above,
3. The EFEM according to claim 2, wherein the supply pipe communicates with a partition wall in a transverse direction when the housing is viewed from above.
The EFEM according to any one of claims 1 to 3, wherein the plurality of supply ports supply inert gas from upstream of the blower.
5. The EFEM according to claim 1, wherein the plurality of supply ports are arranged so as to avoid an upper part of the blower.