JP7140960B2 - 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 it with an inert gas atmosphere.

In Patent Document 1, a load port on which a FOUP (Front-Opening Unified Pod) containing wafers (semiconductor substrates) is mounted and an opening provided in a front wall are connected to the load port to close the load port. , a housing in which a transfer chamber is formed in which wafers are transferred, and wafers are transferred between a processing apparatus that performs a predetermined process on the wafers and a FOUP.

Conventionally, the influence of oxygen, moisture, etc. in the transfer chamber on semiconductor circuits manufactured on wafers was small, but in recent years, with the further miniaturization of semiconductor circuits, these influences have become 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 passage composed of a transfer chamber and a gas return passage for circulating nitrogen inside the housing, and gas supply means for supplying nitrogen to the upper space of the gas return passage. , a plurality of fans arranged in the upper space of the gas return path to send the inert gas to the transfer chamber, and a gas discharge means for discharging nitrogen from the lower part of the gas return path. Nitrogen is appropriately supplied and discharged according to fluctuations in the oxygen concentration and the like in the circulation channel. This makes it possible to keep the inside of the transfer chamber in a nitrogen atmosphere.

JP 2015-146349 A

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, from one supply port. , the pressure on the suction side of the fan varies from fan to fan, and the amount of supply from each fan to the transfer chamber varies. In other words, when inert gas is supplied from one side in the arrangement direction of a plurality of fans, although a sufficient amount of inert gas is supplied to one fan, the amount of inert gas supplied to the other fan is is less than the other. That is, in the upper space, the pressure on the suction side of one fan becomes higher than that of the other fan, causing variation in the amount of inert gas supplied from each fan to the transfer chamber. As a result, there arises a problem that the airflow of the inert gas in the transfer chamber is turbulent, and dust tends to be stirred up.

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

The EFEM of the present invention includes a housing that is closed by connecting a load port to an opening provided in a partition wall and that internally configures a transfer chamber for transferring a substrate; a partition member provided in the housing for forming an upper space above the transfer chamber; and inert gas supply means for supplying an inert gas to the upper space. a plurality of communication ports formed in the partition member for communicating between the transfer chamber and the upper space; and an inert gas in the upper space disposed so as to cover the communication ports, respectively, through the communication ports. to the transfer chamber, a gas suction port provided at the bottom of the transfer chamber for sucking the inert gas in the transfer chamber, and the inert gas sucked from the gas suction port A gas return path for returning to the upper space and gas discharge means for discharging the gas in the transfer chamber are provided. The inert gas supply means has a plurality of supply ports for supplying the inert gas, which are dispersedly arranged in the upper space.

According to this, the inert gas supplied from the inert gas supply means to the upper space can be dispersedly supplied from the plurality of supply ports. As a result, the inert gas can be uniformly supplied to the entire upper space, and variations in pressure on the suction sides of the plurality of blowers in the upper space can be reduced. Therefore, the amount of inert gas supplied from each blower to the transfer chamber is less likely to vary. As a result, in the transfer chamber, it becomes easier to flow the inert gas vertically, and dust is less likely to be stirred up.

In the present invention, the inert gas flows toward a region closest to the supply port in either the partition wall of the housing or the partition member for partitioning the upper space and the outer space. preferably configured to be supplied. As a result, the inert gas supplied from the supply port collides with either the partition member or the partition wall, weakens its momentum, and flows along either the partition member or the partition wall. For this reason, the airflow in the upper space flowing from the gas return path to the blower is less likely to be disturbed, and pressure variations on the suction sides of the plurality of blowers in the upper space are further reduced. 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 gas suction ports are provided in a lower portion 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. and a second flow channel connected to the plurality of first flow channels, and further comprising a delivery port for delivering the gas in the second flow channel to the upper space. is preferred. As a result, the gas from the transfer chamber once flows through the plurality of first flow paths into the second flow path and then 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 is possible to absorb variations in the amount of gas flowing among the plurality of first flow paths. Therefore, the amount of gas delivered from the delivery port is more stable than when the gas is delivered directly from each first flow path to the upper space, and the amount of inert gas supplied from each blower to the transfer chamber is increased. Variation is 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 delivery port is configured to extend between two adjacent first flow paths in the arrangement direction. It is preferable that they are respectively arranged between the roads. As a result, the amount of gas delivered from the delivery port to the upper space is more stable, and variations in the amount of inert gas supplied from each blower to the transfer chamber are further suppressed.

Moreover, in the present invention, it is preferable that the delivery port is arranged at a position sandwiching the blower with the supply port in a cross direction that crosses the array direction of the plurality of blowers. As a result, the airflow in the upper space flowing from the gas return path to the blower is 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 another aspect, the EFEM of the present invention includes: a housing that is closed by connecting a load port to an opening provided in a partition wall, and that internally forms a transfer chamber for transferring a substrate; a partition member provided inside the body for configuring 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; a plurality of blowers for sending gas in the upper space to the transfer chamber; a plurality of gas suction ports provided in a lower portion of the transfer chamber for sucking gas in the transfer chamber; and the gas suction port. and a gas return path for returning the gas sucked from each to the upper space. The gas return path includes a plurality of first flow paths extending from each of the plurality of gas suction ports, and connected to the plurality of first flow paths to allow the gas to flow in from the first flow paths. and a second flow path for delivering the gas to the upper space.

According to this, the gas from the transfer chamber once flows through the plurality of first flow paths into the second flow path and then flows into the upper space. In this way, by causing the gas from the plurality of first flow paths to once flow into the second flow path, it is possible to absorb variations in the flow rate of the gas among the plurality of first flow paths. Therefore, the amount of gas delivered from the delivery port is more stable than when the gas is delivered directly from each first flow path to the upper space, and the variation in the amount of gas supplied from each blower to the transfer chamber is reduced. Suppressed.

Further, in the present invention, the second flow path extends in a direction intersecting the extending direction of the first flow path, and the gas flowing through the gas return path flows from the first flow path It is preferable that the direction of the airflow is changed when flowing through the second channel, and the direction of the airflow is also changed when flowing into the upper space from the second channel. Thereby, in the second flow path, the gas flow in the extending direction of the first flow path can be moderated. Therefore, the airflow in the upper space can be made less likely to be disturbed, compared to the case where the gas directly flows 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 transfer apparatus is arranged in the transfer chamber, and has a base portion whose position is fixed, and a transfer portion that is arranged above the base portion and that transfers the substrate. In the transfer chamber, an installation is arranged below a transfer area in which the substrate is transferred by the transfer unit, and the gas suction port is positioned between the base and the base when viewed in the vertical direction. It may be arranged at a position not overlapping with any of the installation objects.

According to the EFEM of the present invention, it is possible to evenly supply the inert gas to the entire upper space, and to reduce pressure variations on the suction sides of the plurality of blowers in the upper space. Therefore, the amount of inert gas supplied from each blower to the transfer chamber is less likely to vary. As a result, in the transfer chamber, it becomes easier to flow the inert gas vertically, and dust is less likely to be stirred up.

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

An EFEM 1 according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 8. FIG. For convenience of explanation, the directions shown in FIG. 1 are referred to as front, rear, left, and right directions. That is, in the present embodiment, the direction in which the EFEM (Equipment Front End Module) 1 and the substrate processing apparatus 6 are arranged is the front-rear direction, the EFEM 1 side is the front side, and the substrate processing apparatus 6 side is the rear side. Also, 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. Moreover, let the direction orthogonal to both the front-back direction and the left-right direction be an up-down direction.

(Schematic configuration of EFEM and its surroundings)
First, the schematic configuration of the EFEM 1 and its surroundings will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a plan view showing a schematic configuration of an EFEM 1 and its surroundings according to this embodiment. FIG. 2 is a diagram showing the electrical configuration of the EFEM1. 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 controller 5. Behind the EFEM 1 is arranged a substrate processing apparatus 6 for performing a predetermined process on the wafer W (substrate). The EFEM 1 transfers wafers W between a FOUP (Front-Opening Unified Pod) 100 mounted on a load port 4 and a substrate processing apparatus 6 by a transfer robot 3 arranged in a housing 2 . The FOUP 100 is a container that can accommodate a plurality of wafers W arranged vertically, and has 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 traveling automatic guided vehicle: not shown). The FOUP 100 is transferred between the OHT and the load port 4 .

The housing 2 is for connecting the three load ports 4 and the substrate processing apparatus 6 . Inside the housing 2, a transfer chamber 41 is formed which is substantially sealed from the external space and is used to transfer the wafer W without exposing it to the outside air. The transfer chamber 41 is filled with nitrogen when the EFEM 1 is in operation. Although the transfer chamber 41 is filled with nitrogen in this embodiment, it may be an inert gas other than nitrogen (for example, argon). The housing 2 is configured such that nitrogen circulates in the internal space including the transfer chamber 41 (details will be described later). 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 transfer robot 3 is arranged in the transfer chamber 41 and transfers the wafer W. As shown in FIG. The transport robot 3 includes a base unit 90 (see FIG. 3) whose position is fixed, and an arm mechanism 70 (transport unit, see FIG. 3) that is arranged above the base unit 90 and holds and transports the wafer W. and a robot control unit 11 (see FIG. 2). The transfer robot 3 mainly performs operations of taking out the wafers W in the FOUP 100 and transferring them to the substrate processing apparatus 6 and receiving the wafers W processed by the substrate processing apparatus 6 and returning them to the FOUP 100 .

The load port 4 is for mounting 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. As a result, the transfer chamber 41 is configured as a substantially closed space within the housing 2 . Further, the load port 4 is configured to replace the atmosphere inside the FOUP 100 with nitrogen. A door 4a, which is a part of an opening/closing mechanism 54 to be described later, is provided at the rear end of the load port 4. As shown in FIG. The door 4a is opened and closed by a door driving mechanism 55 (a part of the opening and closing mechanism 54). The door 4 a is configured to be able to unlock the lid 101 of the FOUP 100 and to hold the lid 101 . The lid 101 is opened by the door driving mechanism 55 opening the door 4a while the door 4a holds the unlocked lid 101. - 特許庁Thereby, the wafer W in the FOUP 100 can be taken out by the transfer robot 3 . Also, the wafer W can be stored in the FOUP 100 by the transfer robot 3 .

As shown in FIG. 2, the controller 5 is electrically connected to a robot controller 11 of the transfer robot 3, a load port controller 12 of the load port 4, and a controller (not shown) of the substrate processing apparatus 6. , communicates with these controllers. In addition, 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, It grasps information about the atmosphere inside the body 2 . The control device 5 is also electrically connected to a supply valve 112 and a discharge valve 113 (described later), and adjusts the opening of these valves to appropriately adjust the nitrogen atmosphere in the housing 2 .

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

(Case and internal configuration)
Next, the structure of the housing 2 and its interior will be described with reference to FIGS. 3 to 6. FIG. FIG. 3 is a front view when the housing 2 is viewed from the front. FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. FIG. 5 is a cross-sectional view taken along line VV shown in FIG. FIG. 6 is a cross-sectional view taken along line VI-VI shown in FIG. In addition, in FIG.3 and FIG.6, illustration of a partition is abbreviate|omitted. In FIG. 5, illustration of the transfer robot 3 and the like is omitted, and the load port 4 is indicated by a two-dot chain line.

The housing 2 has a substantially rectangular parallelepiped shape as a whole. As shown in FIGS. 3-5, the housing 2 has columns 21-26, a connecting pipe 27, and partition walls 31-36. Partition walls 31 to 36 are attached to columns 21 to 26 extending in the vertical direction, and the internal space (the transfer chamber 41 and the FFU installation chamber 42) of the housing 2 is substantially sealed from 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 sequence from left to right while being separated from each other. That is, the four pillars 21 to 24 are arranged along the horizontal direction. Also, 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 21 b and 24 b are erected on the partition wall 31 and connected to the connecting pipe 27 at their upper ends. The pillars 22 and 23 are also erected on the partition wall 31 and their upper ends are connected to the connecting pipe 27 . The first portions 21b, 24b and the columns 22, 23 have substantially the same vertical length. The second portions 21c and 24c are erected on the connecting pipe 27 at positions overlapping the first portions 21b and 24b in the vertical direction. Two pillars 25 and 26 are vertically arranged 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 pillars 21-24 are arranged) and is connected to the four pillars 21-24.

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 arranged at the front end, a partition 34 is arranged at the rear end, a partition 35 is arranged at the left end, and a partition 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 pillars 21 to 24 in the left-right direction and are closed by the base 51 of the load port 4. As shown in FIG. A mounting portion 83 (see FIG. 3) on which an aligner 84 (to be described later) is mounted is provided at the right end portion of the housing 2 . The aligner 84 and the mounting portion 83 are also accommodated inside the housing 2 (see FIG. 4).

As shown in FIG. 5 , a horizontally extending support plate 37 (partition member) is arranged in the upper portion of the housing 2 and on the rear end side of the connecting pipe 27 . Thereby, the inside of the housing 2 is divided into the transfer chamber 41 described above and the FFU installation chamber 42 formed above the transfer chamber 41 . That is, 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 housing 2 .

Three FFUs (fan filter units) 44 to be described later are arranged in the FFU installation room 42 . Three communication ports 37a for communicating the transfer chamber 41 and the FFU installation chamber 42 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. These three communication ports 37a are arranged side by side along the left-right direction, as shown in FIG. Also, 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 housing 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 end in FIG. 5). (see partition walls 34a, 34b in the section). The number of revolutions 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 air velocity in the transport 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. The number of revolutions of each FFU is determined according to the value of .

Next, the internal configuration of the housing 2 will be described. Specifically, the configuration for circulating nitrogen in the housing 2, the peripheral configuration thereof, and the devices and the like arranged in the transfer chamber 41 will be described.

A configuration for circulating nitrogen in the housing 2 and its peripheral configuration will be described with reference to FIGS. 3 to 6. FIG. As shown in FIG. 5, a circulation path 40 for circulating nitrogen is formed inside the housing 2 . The circulation path 40 is composed of 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 37a, reaches the lower end of the transfer chamber 41, then rises through the return path 43, and enters the FFU installation chamber 42. It is designed to return (see arrow in FIG. 5). A detailed description will be given below.

As shown in FIGS. 5 and 6, the FFU installation room 42 is provided with three FFUs 44 arranged on the support plate 37 and three chemical filters 45 arranged on the FFUs 44 . Each FFU 44, as shown in FIG. 5, has a fan 44a (blower) and a filter 44b, and is arranged on the support plate 37 so as to cover the communication port 37a. 6, the FFU 44 sucks nitrogen in the FFU installation chamber 42 from the periphery of the FFU 44 by the fan 44a and sends it downward, and removes particles (not shown) contained in the nitrogen by the filter 44b. . The chemical filter 45 is for removing active gas or the like 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 delivered 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 to the transfer chamber 41 forms a laminar flow and flows downward.

The return path 43 is formed in the pillars 21 to 24 (the pillar 23 in FIG. 5) arranged at the front end of the housing 2 and the connecting pipe 27 . The interiors of the first portions 21b, 24b of the columns 21, 24, the columns 22, 23, and the connecting pipe 27 are hollow, and spaces 21a to 24a, 27a through which nitrogen can flow are formed respectively ( See Figure 4). The first portions 21b, 24b of the columns 21, 24 are wider than the columns 22, 23 in the horizontal direction, as shown in FIG. That is, the planar size of the spaces 21a and 24a (first flow paths) (that is, the opening areas of the first portions 21b and 24b) is larger than the spaces 22a and 23a (the opening areas of the pillars 22 and 23). The spaces 21a to 24a (first flow paths) are formed to extend in the vertical direction, and all of them extend from the lower ends of the columns 21 to 24 to the positions of the connecting pipes 27. As shown in FIG.

The connecting pipe 27 is arranged at the front end of the housing 2 . A space 27a (second flow path) of the connecting pipe 27 extends in the left-right direction. 5 and 6, communication ports 27b to 27e are formed on the lower surface of the connecting pipe 27 to allow the spaces 21a to 24a and the space 27a to communicate with each other. In addition, as shown in FIG. 6, the upper surface of the connecting pipe 27 is formed with three delivery ports 27f to 27h that open toward the FFU installation chamber 42 (that is, upward). These three delivery 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 elongated in the left-right direction. Also, the three outlets 27f to 27h are arranged at the front end of the housing 2. As shown in FIG. In this way, the connecting pipe 27 is configured so that the nitrogen flowing in from the four spaces 21a to 24a can once be combined and then sent to the FFU installation chamber 42 from the three outlets 27f to 27h. When the nitrogen flows from the spaces 21a to 24a to the space 27a, the direction of the airflow is changed from above to the left and right, and when it flows from the space 27a through the delivery ports 27f to 27h into the FFU installation chamber 42, The direction of the airflow is changed from the horizontal direction to the upward direction. A return path 43 is constituted by such spaces 21a to 24a and 27a. Also, the three delivery ports 27f to 27h are arranged at positions overlapping the FFU 44 along the front-rear direction. That is, the delivery ports 27f to 27h adjacent in the front-rear direction correspond to the FFU 44, respectively. The three outlets 27f to 27h are elongated in the left-right direction and have relatively large opening areas. As a result, the flow of gas delivered from the delivery ports 27f to 27h to the FFU installation chamber 42 becomes gentle, and variations in pressure on the suction side (upper side) of the three FFUs 44 are reduced. The gas delivered from the delivery ports 27f to 27h to the FFU installation chamber 42 flows upward through the space between the partition wall 33 and the FFU 44, as shown in FIG.

The feedback path 43 will be described more specifically with reference to FIG. Although the column 23 is shown in FIG. 5, the first portions 21b and 24b of the other columns 21 and 24 and the column 22 are the same. 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 columns 21, 22, 24. Since the pillars 21 and 24 are formed wider in the horizontal direction than the pillar 23, the introduction duct 28 to which they are attached is also formed wider. An opening 28 a is formed in the introduction duct 28 so that the nitrogen that has reached the lower end of the transfer chamber 41 can flow into the return path 43 . In other words, the opening 28 a is a gas suction port for sucking nitrogen in the transfer chamber 41 to the return path 43 . Further, the opening 28a is configured to face downward. Therefore, the gas reaching the partition wall 31 from above can be smoothly sucked in without disturbing the flow of the gas from above. Furthermore, it is possible to flow the gas sucked through the opening 28a upward without changing the airflow direction.

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

Further, as shown in FIG. 3, a supply pipe for supplying nitrogen into the FFU installation chamber 42 (circulation path 40) is provided at the rear end upper portion of the FFU installation chamber 42 (that is, the rear end portion of the housing 2). 47 are placed. The supply pipe 47 is connected to an external pipe 48 connected to the 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 pipe 48 . The supply pipe 47, the external pipe 48, the supply valve 112 and the supply source 111 constitute inert gas supply means. 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 of only the supply pipe 47 .

As shown in FIGS. 3 and 6, the supply pipe 47 extends in the horizontal direction and has three supply ports 47a. The three supply ports 47 a are arranged apart from each other along the left-right direction, and supply nitrogen from the supply pipe 47 into the FFU installation chamber 42 . These three supply ports 47a are formed at the lower end of the supply pipe 47, as shown in FIGS. (area closest to the supply port 47a). Also, the three supply ports 47a are arranged in the same positional relationship as the center of the FFU 44 in the left-right direction. As a result, the three supply ports 47a are arranged at positions sandwiching the fan 44a between the supply ports 27f to 27h in the front-rear direction.

When nitrogen is supplied from the three supply ports 47a of the supply pipe 47 to the FFU installation chamber 42, since the three supply ports 47a are dispersedly arranged in the FFU installation chamber 42, the nitrogen is supplied to the FFU installation chamber 42. The entire chamber 42 is evenly supplied. For example, when nitrogen is directly supplied into the FFU installation chamber 42 from one supply port of the external pipe 48 connected to the right end of the housing 2, the pressure in the right part of the FFU installation chamber 42 rises. . That is, the pressure on the suction side of the FFU 44 arranged on the rightmost side becomes higher than that of the other two FFUs 44 . If the pressure on the suction side of the FFU 44 greatly varies in this way, the amount of nitrogen supplied from the three FFUs 44 to the transfer chamber 41 tends to vary. However, in this embodiment, nitrogen is supplied from three supply ports 47a that are spaced apart from each other in the left-right direction, so that the pressure variations on the suction sides of the three FFUs 44 are reduced. Therefore, the amount of nitrogen supplied from the three FFUs 44 to the transfer chamber 41 is stabilized, and the nitrogen sent out to the transfer chamber 41 forms a laminar flow and flows downward.

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

The supply valve 112 and the discharge valve 113 are electrically connected to the control device 5 (see FIG. 2). Thereby, it is possible to appropriately supply and discharge nitrogen to the circulation path 40 . For example, when the EFEM 1 is started (including, for example, when the EFME 1 is started after maintenance), if the oxygen concentration in the circulation path 40 is increasing, By supplying nitrogen to the circulation path 40 and discharging 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 lowered. That is, the inside of the circulation path 40 and the storage chamber 60 can be replaced with a nitrogen atmosphere. Even if the oxygen concentration in the circulation path 40 increases while the EFEM 1 is operating, a large amount of nitrogen is temporarily supplied to the circulation path 40, and the oxygen is discharged together with the nitrogen through the discharge pipe 49. can reduce 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 into the circulation path 40 from the outside, the inside of the circulation path 40 is The pressure should be kept slightly higher than the external pressure. Specifically, it is in the range of 1 Pa (G) to 3000 Pa (G), preferably 3 Pa (G) to 500 Pa (G), more preferably 5 Pa (G) to 100 Pa (G). Therefore, when the pressure in the circulation path 40 deviates from the predetermined range, the controller 5 changes the opening of the discharge valve 113 to change the discharge flow rate of nitrogen so that the pressure reaches a predetermined target pressure. adjust to In this manner, 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 differential pressure is adjusted to 10 Pa (G).

Next, devices and the like arranged in the transfer chamber 41 will be described with reference to FIGS. 3 and 4. FIG. As shown in FIGS. 3 and 4, in the transfer chamber 41, the above-described transfer robot 3, control unit storage box 81, measuring device storage box 82, and aligner 84 are arranged. The control unit housing box 81 is installed, for example, on the left side of the base unit 90 (see FIG. 3) of the transport robot 3, below the transport area 200 where the wafer W is transported by the arm mechanism 70 (see FIG. 3). are placed. The robot control unit 11 and the load port control unit 12 described above are housed in the control unit housing box 81 . The measuring instrument storage box 82 is installed, for example, on the right side of the base portion 90 and arranged below the transfer area 200 of the arm mechanism 70 . The measurement equipment storage box 82 can accommodate the measurement equipment (see FIG. 2) such as the oxygen concentration meter 85, the pressure gauge 86, the hygrometer 87, and the like. The control unit storage box 81 and the measuring device storage box 82 correspond to the installation objects of the present invention. The introduction duct 28 (see FIG. 4) described above is arranged in front of the base portion 90, the control unit storage box 81, and the measuring device storage box 82. As shown in FIG. That is, the opening 28a is arranged at a position that does not overlap with any of the base portion 90, the control unit housing box 81, and the measuring equipment housing box 82 when viewed from the top and bottom direction (vertical direction) (FIGS. See Figure 5).

The aligner 84 is for detecting how much 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, the wafer W may slightly move inside the FOUP 100 (see FIG. 1) transported by the 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 at a position shifted from the target holding position, and transmits the measurement result to the robot control unit 11 . Based on the measurement results, the robot control unit 11 corrects the holding position of the arm mechanism 70, 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. be transported. Thereby, the wafer W can be processed normally by the substrate processing apparatus 6 .

(Load port configuration)
Next, the configuration of the load port will be described below with reference to FIGS. 7 and 8. FIG. FIG. 7 is a side cross-sectional view of the load port showing the door closed. FIG. 8 is a side sectional view of the load port showing a state in which the door is opened. 7 and 8 are drawn 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-like base 51 standing vertically and a horizontal base 52 projecting forward from the center of the base 51 in the vertical direction. and A mounting table 53 for mounting the FOUP 100 is provided on the upper portion of the horizontal base portion 52 . The mounting table 53 on which the FOUP 100 is placed can be moved forward and backward by a mounting table driving section (not shown).

The base 51 forms part of the partition wall 33 that isolates the transfer chamber 41 from the external space. The base 51 has a substantially rectangular planar shape elongated in the vertical direction when viewed from the front. Further, the base 51 is formed with a window portion 51a at a position capable of facing the mounted FOUP 100 in the front-rear direction. Further, the base 51 is formed with a vertically extending slit 51b below the horizontal base portion 52 in the vertical direction so that a support frame 56, which will be described later, can move. The slit 51b is formed only in a range in which the support frame 56 can move up and down while passing through the base 51, and the opening width in the horizontal 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 capable of opening/closing the lid 101 of the FOUP 100 . The opening/closing mechanism 54 has 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 to be able to close the window portion 51a. Further, the door 4a is configured to be capable of unlocking the lid 101 of the FOUP 100 and holding the lid 101 . The door drive mechanism 55 includes a support frame 56 for supporting the door 4a, a movable block 58 supporting the support frame 56 so as to be movable in the front-rear direction via slide support means 57, and the movable block 58 mounted on the base 51. and a slide rail 59 supported so as to be movable in the vertical direction.

The support frame 56 supports the lower part of the rear portion of the door 4a, and has a substantially crank-like shape that extends downward, passes through the slit 51b provided in the base 51, and protrudes forward from the base 51. is a plate 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 . In other words, the driving portion for moving the door 4a is outside the housing 2 and is housed in the housing chamber 60 provided below the horizontal base portion 52 . The storage chamber 60 is surrounded by a horizontal base portion 52, a substantially box-shaped cover 61 extending downward from the horizontal base portion 52, and the base 51, and is substantially sealed.

The bottom wall 61a of the cover 61 is connected to the discharge pipe 49 described above. That is, the storage chamber 60 and the discharge pipe 49 are connected. In this embodiment, the accommodation chamber 60 and the discharge pipe 49 are connected to each of the three load ports 4 . As a result, 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. A fan 62 facing the discharge pipe 49 is provided on the bottom wall 61a inside the housing chamber 60. As shown in FIG. Since the fan 62 is provided inside the storage chamber 60 in this way, it is possible to easily discharge the gas from the storage chamber 60 to the discharge pipe 49 while suppressing the particles from being blown up. If a fan were provided to send the gas in the transfer chamber 41 toward the storage chamber 60, the airflow in the transfer chamber 41 would be easily disturbed, and the particles in the transfer chamber 41 would be easily blown up. Since the fan 62 is arranged in the storage chamber 60 in this embodiment, it is possible to suppress the particles in the transfer chamber 41 from being stirred up.

Next, the opening and closing operations of the lid 101 and the 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 rearward to bring the lid 101 and the door 4a into contact with each other. . At this time, the lid 101 of the FOUP 100 is unlocked by the door 4a of the opening/closing mechanism 54, and the lid 101 is held.

Next, as shown in FIG. 8, the support frame 56 is moved rearward. As a result, the door 4a and the lid 101 move backward. By doing so, the lid 101 of the FOUP 100 is opened, the door 4a is opened, and the transfer chamber 41 of the housing 2 and the FOUP 100 are communicated with each other.

Next, as shown in FIG. 8, the support frame 56 is moved downward. As a result, the door 4a and the lid 101 move downward. By doing so, the FOUP 100 is largely opened as a loading/unloading port, and the wafer W can be moved between the FOUP 100 and the EFEM 1 . To close the lid 101 and the door 4a, the operations described above may be performed in reverse order. A series of operations of the load port 4 are controlled by the load port controller 12 .

As described above, according to the EFEM 1 of the present embodiment, since the three supply ports 47a are arranged dispersedly in the FFU installation chamber 42, nitrogen can be supplied evenly throughout the FFU installation chamber 42. becomes possible. Therefore, variations in pressure on the suction side of the fans 44a (blowers) of the three FFUs 44 in the FFU installation room 42 are reduced. Therefore, the amount of nitrogen supplied from each fan 44a to the transfer chamber 41 is stabilized, making it easier to vertically flow nitrogen in the transfer chamber 41 (nitrogen forms a laminar flow), and dust is less likely to be blown up.

Also, 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 that has flowed downward in the transfer chamber 41 can be discharged evenly. This reduces the effect on the laminar flow formed by nitrogen in the transfer chamber 41 . Further, the laminar flow formed by nitrogen in the transfer chamber 41 should be formed at least in the transfer region 200 of the wafer W and above.

In addition, 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 positioned such that the base unit 90 when viewed from the vertical direction. It may be provided at a position that does not overlap with any of the installation objects.

In addition, the inventors of the present application conducted an experiment of laminar flow visualization, and found three points above the transfer robot 3, above the control unit storage box 81, and above the measurement device storage box 82 (points 201, 202, and 203 in FIG. 3). ), the air velocity was measured to confirm the formation of laminar flow. In this embodiment, the number of revolutions of each FFU is determined in advance so that the air velocity in the transport area is 0.3 m/s. As a result, it was confirmed that the backflow of the gas to the transfer area 200 due to the gas colliding with the transfer robot 3 or the like did not occur. Further, 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 gas flow rate difference between the above three points is less than 30%. was confirmed to be 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 installation object was provided in the transport area 200 .

Further, the supply port 47a is configured such that nitrogen is supplied toward the region 37b of the support plate 37 which is closest to the supply port 47a. As a result, the nitrogen supplied from the supply port 47a first hits the area 37b of the support plate 37 and flows along the support plate 37 while its force weakens. For this reason, the airflow in the FFU installation chamber 42 flowing from the delivery ports 27f to 27h to the FFU 44 is less likely to be disturbed, and the pressure variation 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 32 at the ceiling of the housing 2 or the partition 34 at the rear end. Also in this case, similarly to the above, the momentum of nitrogen supplied from the supply port 47a becomes weaker and flows, and the variation in the amount of nitrogen supplied 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 the connecting pipe 27 having the space 27a is formed with delivery ports 27f to 27h. As a result, the gas from the transfer chamber 41 first flows into the space 27a through the four spaces 21a to 24a and then into the FFU installation chamber . More specifically, as shown in FIG. 6, the gas from the space 21a passes through the space 27a toward the delivery port 27f, the gas from the space 22a passes through the space 27a toward the left and right delivery ports 27f and 27g, The gas from the space 23a flows through the space 27a toward the left and right delivery ports 27g and 27h, and the gas from the space 24a flows through the space 27a toward the delivery port 27h. By temporarily flowing the gas from the four spaces 21a to 24a into the space 27a in this way, it is possible to absorb variations in the amount of gas flowing among the four spaces 21a to 24a. In the present embodiment, the opening areas of the spaces 21a and 24a are larger than those of the spaces 22a and 23a. are merged and delivered to the FFU installation chamber 42 from the delivery ports 27f to 27h. Therefore, the amount of gas delivered from the delivery ports 27f to 27h is more stable than when the gas is delivered directly from the spaces 21a to 24a to the FFU installation chamber 42, and the pressure on the suction side of each fan 44a varies. is also suppressed, and variations in the amount of nitrogen supplied from each fan 44a to the transfer chamber 41 are further suppressed.

Since each of the delivery ports 27f to 27h is arranged between two adjacent spaces 21a to 24a in the left-right direction, even if the amount of gas flowing from the two adjacent spaces 21a to 24a varies. 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 delivery ports 27f to 27h is arranged at a position sandwiching the fan 44a with 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 is 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 are possible within the scope of the claims. In the above-described embodiment, the three supply ports 47a formed in the supply pipe 47 are arranged dispersedly in the FFU installation chamber 42. They may be distributed in the chamber 42 . Also, instead of the supply pipe 47 , a porous pipe (such as an air stone) may be arranged in the FFU installation chamber 42 . Also in this case, a plurality of supply ports of the porous pipe are dispersedly arranged in the FFU installation chamber 42, and the same effect as the above-described embodiment can be obtained.

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

Moreover, each delivery port 27f to 27h does not have to be arranged between two adjacent spaces 21a to 24a in the left-right direction. Two or four or more fans 44a (FFUs 44) may be provided. In this case, the communication port 37a may also be formed in the support plate 37 so as to correspond to the fan 44a.

Also, instead of the delivery ports 27f to 27h, for example, a punching metal (not shown) having a large number of holes formed therein may be provided over the entire upper surface of the connecting pipe 27 to change the gas flow.

Further, although the spaces 21a to 24a and 27a formed inside the pillars 21 to 24 and the connecting pipe 27 are assumed to be the return path 43, the return path 43 is not limited to this. That is, the return path 43 may be formed by another member.

1 EFEM
2 housing 3 transfer robot (substrate transfer device)
4 load ports 21a to 24a space (first channel)
27a space (second channel)
27f to 27h delivery 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 exhaust pipe (gas exhaust means)
W Wafer (substrate)

Claims (8)

a housing that is closed by connecting a load port to an opening provided in a partition wall and that internally forms a transfer chamber for transferring substrates;
a substrate transport device arranged in the transport chamber for transporting the substrate;
a partition member provided in the housing for forming an upper space above the transfer chamber;
inert gas supply means for supplying inert gas to the upper space;
a plurality of communication ports formed in the partition member for communicating the transfer chamber and the upper space;
a plurality of blowers arranged to respectively cover the communication ports and for sending the inert gas in the upper space to the transfer chamber through the communication ports;
a gas suction port provided in the lower part of the transfer chamber for sucking the inert gas in the transfer chamber;
a gas return path for returning the inert gas sucked from the gas suction port to the upper space;
and gas discharge means for discharging gas in the transfer chamber,
The inert gas supply means has a plurality of supply ports for supplying the inert gas dispersedly arranged in the upper space.,
The plurality of supply ports are arranged only on the side opposite to the gas return path across the plurality of blowers when viewed from above and below. An EFEM characterized by: The supply port is configured such that the inert gas is supplied toward a region closest to the supply port in either the partition wall of the housing or the partition member for partitioning the upper space and the external space. 2. The EFEM of claim 1, wherein: A plurality of gas suction ports are provided in a lower portion of the transfer chamber,
The gas return path has a plurality of first flow paths extending upward from each of the plurality of gas suction ports, and a second flow path connected to the plurality of first flow paths,
3. The EFEM according to claim 1, further comprising a delivery port for delivering gas in said second flow path to said upper space. The second flow path extends along the arrangement direction of the plurality of first flow paths,
4. The EFEM according to claim 3, wherein the delivery ports are arranged between two adjacent first channels in the arrangement direction. 5. The blower according to claim 3 or 4, wherein the outlet is disposed at a position sandwiching the blower with the supply port in a cross direction crossing the arrangement direction of the plurality of blowers. EFEM. a housing that is closed by connecting a load port to an opening provided in a partition wall and that internally forms a transfer chamber for transferring substrates;
a partition member provided in the housing for forming 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;
a plurality of devices provided in the communication port for sending the gas in the upper space to the transfer chamber;fan filter unitWhen,
a plurality of gas suction ports provided in a lower portion of the transfer chamber for sucking gas in the transfer chamber;
a gas return path for returning the gas sucked from each of the gas suction ports to the upper space;
The gas return path includes a plurality of first flow paths extending from each of the plurality of gas suction ports, and connected to the plurality of first flow paths so that the gas flows in from the first flow paths, a second channel that delivers the gas to the upper space;a delivery port for delivering the gas in the second flow path to the upper space;equipped with,
The delivery port is positioned below upper ends of the plurality of fan filter units. An EFEM characterized by: The second flow path extends in a direction intersecting with the extending direction of the first flow path,
The gas flowing through the gas return path has its direction changed when passing through the second flow path from the first flow path, and when it flows into the upper space from the second flow path, 7. The EFEM of claim 6, wherein the airflow is also redirected. A substrate transfer device having a fixed position base and a transfer unit arranged above the base for transferring the substrate, the device further comprising a substrate transfer device arranged in the transfer chamber,
In the transfer chamber, an installation is arranged below a transfer area in which the substrate is transferred by the transfer unit,
8. The EFEM according to claim 6, wherein the gas suction port is arranged at a position that overlaps neither the base portion nor the installation object when viewed in a vertical direction.

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