TWI867379B - EFEM and gas replacement method of EFEM - Google Patents

Abstract

The present invention is an EFEM and a gas replacement method of the EFEM, and the subject is to suppress the increase of cost and the release of dust into the transfer chamber in an EFEM in which the inactive gas in the frame is circulated. The solution is that the EFEM (1) has: nitrogen purified by the FFU (44) for removing dust flows in a transfer chamber (41) in a specific direction, and a return path (43) from the downstream side of the transfer chamber (41) to return nitrogen to the FFU (44), and the nitrogen is constructed in a circulating manner. The EFEM (1) has: a transfer machine arm (3) arranged in the transfer chamber (41) and performing specific actions while maintaining the state of the wafer. The transfer machine arm (3) comprises: a container component (61) having an opening, an arm mechanism (70) arranged outside the container component (61) for holding a wafer, a support arm mechanism (70), a pillar inserted into the opening, and a driving mechanism received in the container component (61) for driving the pillar, and a connection path (82a) is provided for connecting the container component (61) and the aforementioned return path (43).

Description

EFEM and gas replacement method of EFEM

The present invention relates to an EFEM (Equipment Front End Module) capable of circulating an inert gas.

Patent document 1 discloses an EFEM for transferring wafers between a processing device for performing specific processing on semiconductor substrates (wafers) and a FOUP (Front-Opening Unified Pod) for accommodating wafers. The EFEM comprises a frame having a transfer chamber for transferring wafers, a plurality of loading ports arranged on the outer side of the frame, each of which carries a FOUP, and a transfer device for transferring wafers by running on a rail extending in the transfer chamber.

In the past, the effects of oxygen or moisture in the transfer chamber on semiconductor circuits manufactured on wafers were small, but in recent years, with the miniaturization of semiconductor circuits, such effects have become more pronounced. Therefore, the EFEM described in Patent Document 1 is constructed by filling the transfer chamber with nitrogen, which is an inert gas. Specifically, the EFEM is equipped with: a circulation flow path for circulating nitrogen inside the frame, including the transfer chamber, a gas supply means for supplying nitrogen to the circulation flow path, and a gas exhaust means for exhausting nitrogen from the circulation flow path. Nitrogen is appropriately supplied and exhausted in response to changes in the oxygen concentration in the circulation flow path. This method can maintain a nitrogen environment in the transfer room while suppressing an increase in the nitrogen supply amount, compared with a configuration in which nitrogen is constantly supplied and discharged.

However, in order to suppress the increase in the nitrogen supply and maintain the appropriate atmosphere in the transfer room, it is necessary to install a sensor device that monitors the oxygen concentration or humidity. However, simply installing a sensor device in the transfer room may interfere with the moving transfer device. Therefore, the inventor of this application considered replacing the moving transfer device on the track with a fixed-position transfer device (transfer machine arm) as described in Patent Document 2. Specifically, the transport robot arm comprises: a hollow trunk fixed in the transport chamber, a support column protruding from the trunk, a driving mechanism that drives the support column up and down, and a multi-joint handle mounted on the support column and driven horizontally to hold the wafer for transport. Such a transport robot arm can enter and exit FOUPs placed on multiple loading ports by driving the multi-joint handle horizontally. That is, since there is no rail in the transport chamber and the trunk does not move, its part becomes a part that can ensure the installation space of the sensor equipment, etc. in the transport chamber. [Prior technical literature] [Patent literature]

[Patent Document 1] Japanese Patent Publication No. 2015-146349 [Patent Document 2] Japanese Patent Publication No. 2012-169691

[Problems to be solved by the invention]

In the transfer machine arm described in Patent Document 2, the support supporting the multi-joint handle driven up and down is also used for transferring wafers in the up and down direction. When such a transfer machine arm is applied to the EFEM described in Patent Document 1, the following problems arise. That is, in order to remove dust generated in the trunk when the driving mechanism is operated, when the structure is so constructed that the gas (inactive gas) in the trunk is discharged to the external space outside the EFEM frame, the nitrogen supplied to the transfer chamber is attracted into the trunk through the gap between the trunk and the support, and discharged to the external space. Therefore, it is necessary to supplement the nitrogen for a certain amount, and there is a risk that the supply cost of nitrogen will increase. However, if the structure is such that nitrogen is not discharged from the trunk to the outside, when the support is driven from below (the internal volume of the trunk decreases), the gas (inactive gas) in the trunk is pushed out to the periphery along with the movement of the support. Therefore, there is a risk that the gas (inactive gas) containing dust will be released into the transfer chamber through the above gap.

The purpose of the present invention is to suppress the increase in cost and the release of dust into the transfer room in an EFEM that circulates an inert gas in the frame. [Means for solving the problem]

The EFEM of the first invention is an EFEM having: a transfer chamber in which the inactive gas purified by a fan filter unit for removing dust flows in a specific direction, and a return path for returning the inactive gas to the fan filter unit from the downstream side of the transfer chamber in the specific direction, and the inactive gas is circulated. The EFEM is characterized by having: an automatic device configured in the transfer chamber to hold the substrate and perform specific actions; the automatic device has: a container member formed with an opening, and a holding portion configured on the outside of the container member to hold the substrate, and a supporting portion supporting the holding portion and inserted into the opening, and a driving mechanism housed in the container member to drive the supporting portion, and a connecting path connecting the container member and the return path is provided.

When the support part is driven by the driving mechanism of the automatic device, dust is generated in the internal space of the container member. When the inactive gas containing dust leaks from the gap between the opening of the container member and the support part, there is a possibility that the transfer room is contaminated by the dust. In the present invention, since a connecting path connecting the container member and the return path is provided, even if dust is generated in the internal space of the container member, the dust is discharged to the return path through the connecting path, and the dust leakage into the transfer room can be suppressed. Furthermore, the dust discharged to the return path is removed by the fan filter unit arranged on the downstream side of the return path. As a result, the dust generated in the inner space of the container member can be prevented from polluting the transfer chamber. In addition, in such a configuration, since the inert gas in the container member is not directly discharged to the outside, there is no need to replenish the inert gas discharged from the container member, and the increase in the supply amount of the inert gas can be suppressed, thereby suppressing the increase in cost. As a result, in an EFEM of a type that circulates the inert gas in the frame, it is possible to suppress the increase in cost and suppress the release of dust into the transfer chamber.

The EFEM of the second invention is characterized in that in the first invention, the EFEM is further provided with: a fan for sending the inactive gas in the container member to the return path through the connecting path.

In the present invention, since the inactive gas in the container member can be reliably transferred to the return path through the airflow generated by the fan, leakage of the inactive gas in the container member from the gap between the opening and the support portion can be suppressed, and the release of dust in the transfer room can be more reliably suppressed.

The EFEM of the third invention is characterized in that the EFEM of the second invention is further provided with: a fan driving device for rotationally driving the fan, and a control unit for controlling the fan driving device; the control unit accelerates the rotation speed of the fan when the driving mechanism is in operation by comparing the rotation speed of the fan when the driving mechanism is not in operation.

In the container member, when the driving mechanism is in operation and the support part is driven, dust may be easily generated. In the present invention, when the driving mechanism is in operation, the rotation speed of the fan is accelerated to increase the wind speed, and the inactive gas in the container member can be surely transferred to the return path. In addition, when the driving mechanism is not in operation, the rotation speed of the fan is slowed down, and the power consumption for driving the fan can be reduced.

The EFEM of the fourth invention is characterized in that in any one of the first to third inventions, a conveying machine arm for conveying the substrate is provided as the automatic device, the container assembly is fixed in the conveying chamber, an arm mechanism for holding the substrate and conveying it in a horizontal direction is provided as the holding portion, a pillar for supporting the arm mechanism is provided as the supporting portion, and the pillar is driven up and down by the driving mechanism.

In the present invention, the container component of the conveying machine arm is fixed in the conveying room. That is, since the container part itself is not moved in the conveying room, its part can ensure the space for installing various machines in the conveying room. On the other hand, in the structure of the pillar that drives the arm mechanism up and down, especially when the pillar is driven to be introduced downward, the inactive gas containing the dust generated in the container component is pushed upward along with the movement of the pillar, and there is a possibility that it passes through the gap between the container component and the pillar and is released into the conveying room. In the present invention, even in such a structure, since the container component is connected to the return path via the connecting path, the dust is also discharged to the return path through the connecting path. Accordingly, the inert gas containing dust can be effectively suppressed from flowing into the transfer chamber.

The EFEM of the fifth invention is characterized in that in the fourth invention, the arm mechanism comprises: a robot for holding the substrate, and a switching portion for switching the state of the robot between a holding state for holding the substrate and a releasing state for releasing the holding state, and the dust generated during the operation of the switching portion is attracted by the flow of the inactive gas supplied from an inactive gas supply source for dust removal, and the inactive gas supplied is discharged together with the dust from the ejector of the return path.

When the robot is switched between the holding state and the releasing state via the switching portion, if dust is generated, there is a risk that the dust will adhere to the substrate. Here, in order to remove the dust, when a vacuum exhaust is formed, since the inactive gas is exhausted from the transfer chamber, a part of the inactive gas must be replenished, and there is a risk that the cost will increase. In the present invention, the dust is sucked by the ejector, and the inactive gas supplied from the inactive gas supply source is discharged to the return path at the same time as the dust, so the inactive gas is directly circulated. Furthermore, the dust is removed via the fan filter unit. Accordingly, compared with the structure of vacuum exhaust, the increase in the cost of replenishing the inactive gas can be suppressed.

The EFEM of the 6th invention is characterized in that in the aforementioned 4th or 5th invention, the aforementioned arm mechanism has a hollow arm component, and the aforementioned arm component is formed with an inlet for allowing the aforementioned inactive gas supplied by the inactive gas supply source for self-purification to flow into the internal space of the aforementioned arm component, and an outlet for allowing the aforementioned inactive gas to flow out from the aforementioned internal space of the aforementioned arm component.

The arm member of the conveyor machine arm generally has a hollow structure in order to house a driving mechanism. The internal space of the arm member can be completely sealed with respect to the conveying chamber, but in a structure that is not such, when the conveying chamber is released to the atmosphere during maintenance, for example, the internal space of the arm member is also released to the atmosphere, and there is a possibility that oxygen or moisture may enter the internal space. In this case, when the arm member is restarted after maintenance, it takes time to replace the inactive gas in the arm member, and there is a possibility that the production efficiency may decrease. In the present invention, since an inlet and an outlet are formed in the arm member, the time taken to replace the gas in the internal space of the arm member can be shortened compared to a case where such an inlet and an outlet are not formed, and the decrease in production efficiency can be suppressed.

The gas replacement method of the EFEM of the seventh invention comprises: the inactive gas purified by the fan filter unit for removing dust flows into the transfer chamber in a specific direction, and a return path from the downstream side of the transfer chamber in the aforementioned specific direction returns the inactive gas to the fan filter unit. The gas replacement method for replacing the gas in the EFEM in which the inactive gas is circulated is characterized in that the EFEM The invention is provided with an automatic device which is arranged in the aforementioned transfer chamber and performs specific actions while maintaining the state of the substrate, and the aforementioned automatic device comprises a container component formed with an opening, and a driving device accommodated in the aforementioned container component, which supplies the aforementioned inactive gas to the interior of the aforementioned container component from the aforementioned inactive gas supply source, sends the gas from the interior of the aforementioned container component to the aforementioned return path, and replaces the gas inside the aforementioned container component.

In the present invention, for example, when the EFEM is started, the gas in the container member can be quickly replaced by actively supplying the inactive gas from the supply source. In addition, since the gas is sent from the inside of the container member to the return path, when the EFEM is started, the dust in the container member can be suppressed from being released into the transfer room.

The gas replacement method of the EFEM of the eighth invention is characterized in that in the seventh invention, after the aforementioned gas environment in the aforementioned transfer chamber becomes less than a specific oxygen concentration, the supply of the aforementioned inactive gas from the aforementioned supply source is stopped, and thereafter, the gas in the aforementioned transfer chamber is introduced into the interior of the aforementioned container component and sent to the aforementioned return path.

In the present invention, the inert gas is not normally supplied from the supply source to the container member, but the gas is introduced from the transfer chamber into the container member and then sent to the transfer path, thereby suppressing the increase in cost. In addition, since the backflow of the gas from the container member to the transfer chamber can be suppressed, the dust in the container member can be suppressed from being released into the transfer chamber.

Hereinafter, the implementation form of the present invention will be described with reference to FIG. 1 to FIG. 8 . However, for the convenience of description, the direction shown in FIG. 1 is taken as the front-rear and left-right directions. That is, the direction in which the EFEM (Equipment Front End Module) 1 and the substrate processing device 6 are arranged is taken as the front-rear direction. The side of the EFEM 1 is taken as the front, and the side of the substrate processing device 6 is taken as the rear. The direction in which a plurality of loading ports 4 are arranged orthogonal to the front-rear direction is taken as the left-right direction. In addition, the direction orthogonal to both the front-rear direction and the left-right direction is taken as the up-down direction.

(Schematic structure of EFEM and its periphery) First, the schematic structure of EFEM1 and its periphery is explained using FIG. 1 and FIG. 2. FIG. 1 is a schematic plan view of EFEM1 and its periphery related to the present embodiment. FIG. 2 is a diagram showing the electrical structure of EFEM1. As shown in FIG. 1, EFEM1 comprises: a frame 2, a transfer robot arm 3, a plurality of loading ports 4, and a control device 5. A substrate processing device 6 for performing specific processing on a wafer W (substrate of the present invention) is arranged at the rear of EFEM1. EFEM1 transfers wafer W between a FOUP (Front-Opening Unified Pod) 100 mounted on the loading port 4 and the substrate processing device 6 via the transfer robot arm 3 arranged in the frame 2. FOUP100 is a container that can accommodate multiple wafers W arranged in the vertical direction, and is equipped with a cover 101 at the rear end (the end of the frame 2 side in the front-to-back direction). FOUP100 is, for example, suspended on a track (not shown) set above the loading port 4 and is transported by an OHT (overhead unmanned transport vehicle) (not shown). FOUP100 is transferred between the OHT and the loading port 4.

The frame 2 is configured to connect a plurality of loading ports 4 and a substrate processing device 6. A transfer chamber 41 is formed inside the frame 2, which is slightly closed to the outside space and is used to transfer wafers W. When the EFEM 1 is operated, the transfer chamber 41 is filled with nitrogen (the inactive gas of the present invention). The frame 2 is configured so that nitrogen circulates in the internal space including the transfer chamber 41 (details will be described later). In addition, a door 2a is installed at the rear end of the frame 2, and the transfer chamber 41 is connected to the substrate processing device 6 through the door 2a.

The transfer robot arm 3 is arranged in the transfer chamber 41 to transfer the wafer W. The transfer robot arm 3 has: a fixed position base part 60 (refer to FIG. 3), an arm mechanism 70 (refer to FIG. 3) arranged above the base part 60 to hold the wafer W for transfer, and a robot arm control part 11 (refer to FIG. 2). The transfer robot arm 3 mainly performs the action of taking out the wafer W in the FOUP 100 and delivering it to the substrate processing device 6, or receiving the wafer W processed by the substrate processing device 6 and returning it to the FOUP 100.

The loading port 4 is configured to load FOUP100 (refer to Figure 5). The plurality of loading ports 4 are arranged in the left-right direction with the rear end portions thereof being adjacent to each other along the front side of the frame 2. The loading port 4 is configured so that the ambient gas in the FOUP100 can be replaced with an inactive gas such as nitrogen. A door 4a is provided at the rear end portion of the loading port 4. The door 4a is opened and closed by a door opening and closing mechanism not shown. The door 4a is configured so that the lock of the cover 101 of the FOUP100 can be released and the cover 101 can be maintained. When the door 4a maintains the unlocked state of the cover 101, the door 4a is opened by the door moving mechanism, and the cover 101 is opened. As a result, the wafer W in the FOUP 100 can be taken out by the transfer robot arm 3 .

As shown in FIG2 , the control device 5 is electrically connected to the robot arm control unit 11 of the transfer robot arm 3, the control unit of the loading port 4 (not shown), and the control unit of the substrate processing device 6 (not shown), and communicates with these control units. In addition, the control device 5 is electrically connected to the oxygen concentration meter 55, the pressure gauge 56, the humidity meter 57, etc. installed in the frame 2, receives the measurement results of these measuring devices, and grasps the information about the ambient air in the frame 2. In addition, the control device 5 is electrically connected to the supply valve 112 and the exhaust valve 113 (described later), and the ambient air in the frame 2 is appropriately adjusted by adjusting the opening of these valves.

As shown in FIG. 1 , the substrate processing device 6 includes, for example, a load interlocking vacuum chamber 6a and a processing chamber 6b. The load interlocking vacuum chamber 6a is connected to the transfer chamber 41 via the door 2a of the frame 2, and is a chamber for temporarily placing the wafer W on standby. The processing chamber 6b is connected to the load interlocking vacuum chamber 6a via the door 6c. In the processing chamber 6b, a specific process is applied to the wafer W via a processing mechanism not shown in the figure.

(Frame and its internal structure) Next, the frame 2 and its internal structure are described using Figures 3 to 5. Figure 3 is a front view of the frame 2. Figure 4 is a cross-sectional view taken along line IV-IV in Figure 3. Figure 5 is a cross-sectional view taken along line V-V in Figure 3. However, the illustration of the partition wall is omitted in Figure 3. In addition, the illustration of the transport machine arm 3, etc. is omitted in Figure 5.

The frame 2 is a rectangular parallelepiped as a whole. As shown in FIG. 3 to FIG. 5, the frame 2 has columns 21 to 26 and partitions 31 to 36. The partitions 31 to 36 are installed on the columns 21 to 26 extending in the up-down direction, and the internal space of the frame 2 is slightly closed to the external space.

More specifically, as shown in FIG4 , at the front end of the frame 2, columns 21 to 24 are arranged in sequence from left to right and are arranged upright. Columns 22 and 23 arranged between columns 21 and 24 are shorter than columns 21 and 24. Columns 25 and 26 are arranged upright on the left and right sides of the rear end of the frame 2.

As shown in FIG3 , a partition wall 31 is disposed at the bottom of the frame 2, and a partition wall 32 is disposed at the top. As shown in FIG4 , a partition wall 33 is disposed at the front end, a partition wall 34 is disposed at the rear end, a partition wall 35 is disposed at the left end, and a partition wall 36 is disposed at the right end. A carrier 53 (see FIG3 ) on which an aligner 54 described later is disposed is provided at the right end of the frame 2. The aligner 54 and the carrier 53 are also accommodated inside the frame 2 (see FIG4 ).

As shown in FIG. 3 and FIG. 5, a support plate 37 extending in the horizontal direction is arranged on the upper side portion of the frame 2 (above the columns 22, 23). Through this, the interior of the frame 2 is divided into the aforementioned transfer chamber 41 formed on the lower side, and the FFU installation chamber 42 formed on the upper side. The FFU installation chamber 42 is arranged with the FFU (fan filter unit) 44 described later. An opening 37a connecting the transfer chamber 41 and the FFU installation chamber 42 is formed in the central portion in the front-rear direction of the support plate 37. However, the partitions 33 to 36 of the frame 2 are divided into the lower wall for the transfer chamber 41 and the upper wall for the FFU installation chamber 42 (for example, refer to the partitions 33a, 33b at the front end and the partitions 34a, 34b at the rear end in FIG. 5).

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

The structure for circulating nitrogen in the frame 2 and its peripheral structure are explained using Figures 3 to 5. As shown in Figure 5, a circulation path 40 for circulating nitrogen is formed inside the frame 2. The circulation path 40 is constructed through a transfer chamber 41, an FFU installation chamber 42, and a return path 43. As a summary, in the circulation path 40, clean nitrogen is sent out from the FFU installation chamber 42 to the bottom, and after reaching the lower end of the transfer chamber 41, it rises through the return path 43 and returns to the FFU installation chamber 42 (refer to the arrow in Figure 5). The following is a detailed description.

The FFU installation chamber 42 is provided with an FFU 44 disposed on a support plate 37 and a chemical filter 45 disposed on the FFU 44. The FFU 44 has a fan 44a and a filter 44b. The FFU 44 sends nitrogen in the FFU installation chamber 42 downward through the fan 44a, and removes dust (not shown) contained in the nitrogen through the filter 44b. The chemical filter 45 is configured to remove, for example, active gas brought into the circulation path 40 from the substrate processing device 6. The nitrogen purified by the FFU 44 and the chemical filter 45 is sent from the FFU installation chamber 42 to the transfer chamber 41 through the opening 37a formed in the support plate 37. The nitrogen system sent out of the transfer chamber 41 forms a laminar flow and flows downward.

The return path 43 is formed in the columns 21 to 24 (the columns 23 in FIG. 5 ) and the support plate 37 disposed at the front end of the frame 2. That is, the columns 21 to 24 are hollow, and each has a space 21a to 24a (see FIG. 4 ) through which nitrogen passes. That is, the spaces 21a to 24a each constitute the return path 43. The return path 43 is connected to the FFU installation chamber 42 through the opening 37b formed at the front end of the support plate 37 (see FIG. 5 ).

The return path 43 will be described in more detail with reference to FIG5 . However, FIG5 shows the column 23, but the same is true for the other columns 21, 22, and 24. An introduction conduit 27 is installed at the lower end of the column 23 to facilitate the flow of nitrogen in the transfer chamber 41 into the return path 43 (space 23a). An opening 27a is formed in the introduction conduit 27, and the nitrogen reaching the lower end of the transfer chamber 41 can flow into the return path 43. An expansion portion 27b is formed at the upper portion of the introduction conduit 27, which expands more toward the rear as it goes downward. A fan 46 is arranged below the expansion portion 27b. The fan 46 is driven by a motor (not shown) to suck the nitrogen that has reached the lower end of the transfer chamber 41 into the return path 43 (space 23a in FIG. 5 ) and send it upward to return the nitrogen to the FFU installation chamber 42. The nitrogen returned to the FFU installation chamber 42 is purified by the FFU 44 or the chemical filter 45 and sent out again to the transfer chamber 41. As a result, the nitrogen can circulate in the circulation path 40.

In addition, as shown in FIG3 , a supply pipe 47 for supplying nitrogen into the circulation path 40 is connected to the side of the FFU installation chamber 42. The supply pipe 47 is connected to a nitrogen supply source 111. A supply valve 112 that can change the supply amount of nitrogen per unit time is provided in the middle of the supply pipe 47. In addition, as shown in FIG5 , an exhaust pipe 48 for exhausting the gas in the circulation path 40 is connected to the front end of the transfer chamber 41. The exhaust pipe 48 is connected to the external space. A exhaust valve 113 that can change the exhaust amount of the gas in the circulation path 40 per unit time is provided in the middle of the exhaust pipe 48. The supply valve 112 and the exhaust valve 113 are electrically connected to the control device 5 (refer to FIG2 ). This allows nitrogen to be appropriately supplied and discharged to the circulation path 40. For example, when the oxygen concentration in the circulation path 40 increases, more nitrogen may be temporarily supplied to the circulation path 40 from the supply source 111 through the supply pipe 47, and oxygen may be discharged together with nitrogen through the discharge pipe 48 to reduce the oxygen concentration.

Next, the machines and the like arranged in the transfer chamber 41 are explained using FIG. 3 and FIG. 4. As shown in FIG. 3 and FIG. 4, the transfer chamber 41 is provided with the above-mentioned transfer machine arm 3, a control unit storage box 51, a measuring machine storage box 52, and an aligner 54. The structure of the transfer machine arm 3 will be described later. The control unit storage box 51 is, for example, disposed on the left side of the base portion 60 (refer to FIG. 3) of the transfer machine arm 3, and is arranged so as not to interfere with the arm mechanism 70 (refer to FIG. 3). The control unit storage box 51 accommodates the above-mentioned machine arm control unit 11. The measuring machine storage box 52 is, for example, disposed on the right side of the base portion 60, and is arranged so as not to interfere with the arm mechanism 70. The measuring device storage box 52 is used to store the above-mentioned measuring devices such as the oxygen concentration meter 55, the pressure gauge 56, the humidity meter 57, etc. (refer to FIG. 2).

The aligner 54 is configured to detect how much the holding position of the wafer W held by the arm mechanism 70 (see FIG. 3 ) of the transport robot arm 3 deviates from the target holding position. For example, in the interior of the FOUP 100 (see FIG. 1 ) transported by the above-mentioned OHT (not shown), the wafer W may move slightly. Therefore, the transport robot arm 3 temporarily places the wafer W before processing taken out from the FOUP 100 on the aligner 54. The aligner 54 measures how much the wafer W is held by the transport robot arm 3 and deviates from the target holding position, and sends the measurement result to the robot arm control unit 11. The robot arm control unit 11 corrects the holding position of the arm mechanism 70 according to the above measurement results, controls the arm mechanism 70 to hold the wafer W at the target holding position, and transports it to the load interlock vacuum chamber 6a of the substrate processing device 6. In this way, the wafer W passing through the substrate processing device 6 can be processed normally.

(Construction of the transport machine arm) Next, the structure of the transport machine arm 3 (automatic device of the present invention) is described using FIG6. FIG6 (a) is a cross-sectional view showing the internal structure of the transport machine arm 3. FIG6 (b) is a plan view of the robot hand 74 described later. As described above, the transport machine arm 3 has a base portion 60 and an arm mechanism 70 (holding portion of the present invention).

As shown in FIG6(a), the base portion 60 is provided with a container member 61, a support 62, and a driving mechanism 63. The support 62 protruding upward from the container member 61 supports the arm mechanism 70. The support 62 is driven up and down by the driving mechanism 63.

The container member 61 is a cylindrical member extending in the vertical direction. The container member 61 is fixed in the transfer chamber 41. An opening 61a is formed on the upper surface of the container member 61 for inserting the support 62. The support 62 is a columnar member protruding upward from the inner side of the container member 61 through the opening 61a. There is a gap between the support 62 and the opening 61a. An arm mechanism 70 is installed on the upper end of the support 62.

The driving mechanism 63 includes, for example, a motor 64, a belt 65, a rolling screw shaft 66, and a slider 67. The power of the motor 64 is transmitted to the rolling screw shaft 66 through the belt 65, and the rolling screw shaft 66 extending in the vertical direction rotates. When the rolling screw shaft 66 rotates, the slider 67 screwed to the rolling screw shaft 66 moves up and down, causing the support column 62 to move up and down.

The motor 64 is a general AC motor having a rotating shaft 64a. The motor 64 is controlled by the machine arm control unit 11 (see FIG. 2 ). A pulley (not shown) is installed at the front end of the rotating shaft 64a, and a belt 65 is wound around it. The rolling screw shaft 66 extends in the up-down direction. A pulley (not shown) is installed at the lower end of the rolling screw shaft 66, and a belt 65 is wound around it. The rolling screw shaft 66 is formed with an external thread (not shown). The slider 67 is a component that supports the support column 62. The slider 67 is formed with an internal thread (not shown) that is screwed with the external thread of the rolling screw shaft 66. The slider 67 is movable up and down along a guide (not shown) extending in the vertical direction as the rolling screw shaft 66 rotates. The support 62 is driven up and down by the driving mechanism 63 having the above structure. Thus, the wafer W stored in the FOUP 100 at a specific position in the vertical direction can be held by the arm mechanism 70.

As shown in FIG. 6( a ), the arm mechanism 70 has, as an example, three arm members 71 to 73 and two robot arms 74. The arm mechanism 70 is supported from below by a support 62 , and the arm members 71 to 73 rotate to horizontally move the robot arm 74 holding the wafer W. However, only one robot arm 74 may be provided.

The arm members 71 to 73 are hollow members extending in a specific direction. That is, the arm members 71, 72, and 73 each have an internal space 71a, 72a, and 73a. However, the internal spaces 71a, 72a, and 73a are connected via a gap. The arm members 71, 72, and 73 are arranged in this order from below. One end of the arm member 71 is rotatably connected to the support 62, and the other end is rotatably connected to one end of the arm member 72. The other end of the arm member 72 is rotatably connected to one end of the arm member 73. The other end of the arm member 73 is rotatably connected to the robot 74. The arm members 71 to 73 and the robot 74 are each rotationally driven in the horizontal direction by a motor not shown.

As shown in FIG. 6( b ), the robot 74 has a loading member 75, protrusions 76a to 76d, and a movable portion 77 (a switching portion of the present invention). A wafer W is loaded on the loading member 75 extending in the extending direction of the robot 74 (see FIG. 6( b )). The wafer W is held by the protrusions 76a and 76b disposed on the front end side of the loading member 75, the protrusions 76c and 76d disposed on the base end side of the loading member 75, and the pressing portion 78 disposed on the front end of the movable portion 77. In this way, the wafer W is held by the robot 74. The movable portion 77 is moved in the extending direction of the robot 74 via a sleeve 79 built into the robot 74. The rod (not shown) of the sleeve 79 is configured to be retractable in the extending direction by supplying nitrogen from a supply source 114 other than the supply source 111 (see FIG. 3 ). When nitrogen is supplied to the sleeve 79 and the pressing portion 78 is located at the front end side (see the solid line in FIG. 6 (b)), the wafer W is pressed by the pressing portion 78 to be held (holding state). When nitrogen is not supplied to the sleeve 79 and the pressing portion 78 is located at the base end side (see the two-point lock chain in FIG. 6 (b)), the holding state is released (released state).

When the transfer machine arm 3 having the above structure is applied to the EFEM 1, the following problems arise. First, in the base part 60, when the support 62 is driven up and down by the driving mechanism 63, dust is generated inside the container member 61. The generated dust may pass through the gap between the opening 61a and the support 62 and leak into the transfer chamber 41. In particular, as shown by the arrow in Figure 6 (a), when the support 62 is driven while being retracted downward by the driving mechanism 63, the nitrogen in the container member 61 is pushed upward, and the nitrogen containing dust may be dispersed in the transfer chamber 41 through the above gap.

In addition, when the movable part 77 of the robot 74 is driven through the sleeve 79, dust may be generated in the transfer chamber 41. In order to remove the dust, nitrogen is discharged from the transfer chamber 41 during exhaust. Part of the nitrogen must be replenished from the supply source 111, which may increase the cost.

In addition, in the structure where the internal spaces 71a to 73a of the arm members 71 to 73 are not completely sealed with respect to the transfer chamber 41, for example, when the atmosphere is released into the transfer chamber 41 during maintenance, the internal spaces 71a to 73a are also released by the atmosphere, and there is a risk of oxygen or moisture entering. In this case, when the nitrogen replacement of the internal spaces 71a to 73a is taken time when restarting after maintenance, there is a risk of a decrease in production efficiency. Therefore, EFEM1 has the following structure to solve these problems.

(Nitrogen discharge path in the transfer machine arm, etc.) The nitrogen discharge path in the transfer machine arm 3 is described using FIG. 7 and FIG. 8. FIG. 7 is a schematic diagram showing the nitrogen supply path and discharge path for the circulation path 40. FIG. 8 is a diagram showing the nitrogen discharge port in the transfer machine arm 3.

First, the structure for discharging nitrogen containing dust from the container member 61 of the conveyor arm 3 is described. As shown in Figures 7 and 8, a delivery port 61b is formed on the side of the container member 61 for delivering nitrogen to the circulation path 40. Furthermore, a delivery portion 81 is provided in the frame 2 for delivering nitrogen from the container member 61 to the circulation path 40. The delivery portion 81 has a connection path 82a formed by a connection tube 82, a fan 83 (the fan of the present invention), and a motor 84 (the fan driving device of the present invention). The connection path 82a connects the container member 61 and the return path 43. The connection path 82a is connected to the upstream end of the return path 43 extending from the delivery port 61b of the container member 61 in the flow direction of nitrogen (more specifically, upstream of the fan 46). In other words, the container member 61 and the return path 43 are directly connected without passing through the transfer chamber 41. The fan 83 is arranged near the delivery port 61b and is driven to rotate at a certain rotation speed by the motor 84.

By the above-mentioned structure, the nitrogen in the container member 61 is delivered to the return path 42 through the delivery port 61b (refer to the arrows 201 and 202 in FIG8). By this, the dust generated in the container member 61 is prevented from contaminating the transfer chamber 41. In addition, since the nitrogen in the container member 61 is not directly discharged to the outside of the frame 2, it is not necessary to immediately replenish the nitrogen discharged from the container member 61, and the increase in the nitrogen supply amount is suppressed. In addition, since the airflow generated by the fan 83 reliably transfers the nitrogen in the container member 61 to the return path, the nitrogen in the container member 61 is prevented from leaking from the gap between the opening 61a (refer to FIG6 (a)) and the support 62 (refer to FIG6 (a)).

Next, the structure for removing dust generated when the movable part 77 of the robot 74 is driven through the sleeve 79 will be described. As shown in FIG7, the EFEM 1 is provided with a suction part 86 for removing dust generated by the action of the sleeve 79. The suction part 86 has an ejector 87 for removing dust by suction through nitrogen supplied from a supply source 115 (an inactive gas supply source for dust removal of the present invention) other than the supply sources 111 and 114 (see FIG6(b)). The ejector 87 has a nozzle 87a, a diffuser 87b, and an ejector port 87c. The ejector 87 generates negative pressure at the suction port 87c by the flow of nitrogen ejected from the nozzle 87a toward the diffuser 87b. The nozzle 87a is connected to the supply path 88a through which nitrogen supplied from the supply source 115 flows. The diffuser 87b is connected to the delivery path 88b for delivering nitrogen to the circulation path 40. The downstream side end of the delivery path 88b is connected to the middle of the connecting path 82a and merges with the delivery part 81. The suction port 87c is connected to the suction path 88c extending from the vicinity of the sleeve 79.

In the suction part 86 having the above structure, nitrogen is supplied to the ejector 87 from the supply source 115, and dust generated by the operation of the sleeve 79 is sucked through the suction path 88c. Furthermore, the supplied nitrogen flows into the connection path 82a through the delivery path 88b at the same time as the sucked dust, and is then delivered to the return path 43. That is, the nitrogen is not directly discharged to the external space of the frame 2 but temporarily flows into the circulation path 40.

Next, the structure of the internal space 71a~73a (refer to Figure 8) of the arm components 71~73 of the transfer machine arm 3 for nitrogen replacement is explained. As shown in Figures 7 and 8, the transfer machine arm 3 is provided with a replacement path 91 passing through the inside of the arm components 71~73. The replacement path 91 has a supply path 91a and an internal passage 91b (refer to Figure 8). The supply path 91a extends from a supply source 116 (an inert gas supply source for purification of the present invention) which is separate from the above-mentioned supply sources 111, 114, and 115, and nitrogen supplied from the supply source 116 flows. The supply path 91a is formed of, for example, a flexible hose, and passes through the interior of the container member 61 and the interior of the arm members 71 to 73. The front end of the supply path 91a is disposed in the internal space 73a of the uppermost arm member 73. That is, nitrogen is first supplied to the internal space 73a of the arm member 73 through the supply path 91a. The internal passage 91b is disposed on the downstream side of the supply path 91a in the flow direction of nitrogen, and is a passage for nitrogen including the internal spaces 71a to 73a.

An example of the internal passage 91b will be described with reference to FIG8 . The arm members 71 to 73 are each formed with an inlet 71b to 73b for the inflow of nitrogen, and an outlet 71c to 73c for the outflow of gas. More specifically, it is as follows. That is, near the inlet 73b formed at the lower portion of the arm member 73, the front end portion of the supply path 91a is installed. The internal space 73a of the arm member 73 is connected to the supply path 91a. The internal space 72a of the arm member 72 is connected to the internal space 73a via the outlet 73c and the inlet 72b. The internal space 71a of the arm member 71 is connected to the internal space 72a via the outlet 72c and the inlet 71b. The inner space 71a is connected to the interior of the container member 61 through the outflow port 71c. Thus, the nitrogen supplied from the supply source 116 through the supply path 91a to the inner space 73a sequentially passes through the inner spaces 73a, 72a, and 71a, flows into the interior of the container member 61, and is transferred to the return path 42 through the delivery port 61b.

Next, a method for replacing the gas inside the transfer machine arm 3 is described. First, for example, when the EFEM 1 is activated, nitrogen is delivered to the internal space 73a of the arm member 73 through the supply path 91a from the supply source 116 (refer to FIG. 7 , the supply source of the present invention), and nitrogen is then supplied to the inside of the container member 61 through the internal spaces 72a and 71a (refer to FIG. 8 ). Furthermore, the gas inside the container member 61 is delivered to the return path 43 through the delivery port 61b. Thus, the gas inside the container member 61 is quickly replaced with nitrogen. Furthermore, after the nitrogen concentration in the transfer chamber 41 becomes less than a specific value (for example, less than 100 ppm), the supply of nitrogen from the supply source 116 is stopped. Normally, the fan 83 is driven by rotation to introduce gas from the transfer chamber 41 into the container member 61 through the opening 61a, etc., and the gas in the container member 61 is sent out to the return path 43. Thus, dust is suppressed from being released into the transfer chamber 41.

As described above, the connection path 82a connecting the container member 61 of the transfer machine arm 3 and the return path 43 is provided. Therefore, even if dust is generated in the internal space of the container member 61, the dust is discharged to the return path 43 through the connection path 82a, and the dust can be suppressed from leaking into the transfer chamber 41. Furthermore, the dust discharged to the return path 43 is removed by the FFU 44 arranged on the downstream side of the return path 43. Accordingly, the dust generated in the internal space of the container member 61 can be suppressed from contaminating the transfer chamber 41. In addition, in such a configuration, since the nitrogen in the container member 61 is not directly discharged to the outside, it is not necessary to replenish the nitrogen discharged from the container member 61, and the increase in the nitrogen supply amount can be suppressed, thereby suppressing the increase in cost. Accordingly, in the EFEM 1 of the form in which the nitrogen in the frame 2 is circulated, the increase in cost can be suppressed, and the release of dust in the transfer chamber 41 can be suppressed. In addition, when the EFEM 1 is started, for example, by actively supplying inert gas from the supply source 116, the gas in the container member 61 can be quickly replaced. In addition, after the oxygen concentration in the transfer chamber 41 becomes less than a specific value, the supply of nitrogen from the supply source 116 is stopped, thereby suppressing the increase in cost.

In addition, since the nitrogen in the container member 61 can be reliably transferred to the return path 43 through the airflow generated by the fan 83, leakage of nitrogen in the container member 61 from the gap between the opening 61a and the support 62 can be suppressed, and the release of dust in the transfer chamber 41 can be more reliably suppressed.

In addition, the dust generated near the sleeve 79 is sucked by the ejector 87, and the nitrogen supplied from the supply source 115 is discharged to the return path 43 together with the dust, so that the nitrogen is directly circulated. Furthermore, the dust is removed by the FFU 44. Accordingly, compared with the configuration of vacuum exhaust, the increase in the cost of nitrogen replenishment can be suppressed.

In addition, since the container components 71~73 are each formed with an inlet 71b~73b and an outlet 71c~73c, compared with the case where these are not formed, the time spent on gas replacement in the internal space 71a~73a of the arm components 71~73 can be shortened, and the decline in production efficiency can be suppressed.

Next, the modified examples of the above-mentioned embodiments are described. However, for those having the same structure as the above-mentioned embodiments, the same symbols are attached and the description thereof is omitted as appropriate.

(1) In the aforementioned embodiment, the fan 83 is driven to rotate at a certain rotation speed via the motor 84, but the present invention is not limited thereto. In the container member 61, the driving mechanism 63 may easily generate dust when driving the support 62 up and down. Therefore, as shown in FIG9 , the conveyor arm 3a may have a fan control unit 12 (control unit of the present invention) for controlling the motor 84. Furthermore, the fan control unit 12 may accelerate the rotation speed of the fan 83 when the driving mechanism 63 is in operation, compared with when the driving mechanism 63 is not in operation. Thus, when the driving mechanism 63 is in operation, the wind speed is accelerated by accelerating the rotation speed of the fan 83, so that the nitrogen in the container member 61 can be reliably transferred to the return path 43. In addition, when the drive mechanism 63 is not in operation, the power consumption of the motor 84 can be reduced by slowing down the rotation speed of the fan 83. However, the control device 5 (see FIG. 1, etc.) or the robot arm control unit 11 (see FIG. 2, etc.) may be configured to control the rotation speed of the fan 83.

(2) In the embodiments described above, the container member 61 of the transport robot arm 3 and the return path 43 are connected via the connection path 82a (that is, the transport robot arm 3 is equivalent to the automatic device of the present invention), but the present invention is not limited to this. For example, the present invention may also be applied to the aligner 54 described above. In this case, the aligner 54 is also equivalent to the automatic device of the present invention. The following is a specific explanation using FIG. 10. FIG. 10(a) is a partial cross-sectional view showing the structure of the aligner 54. FIG. 10(b) is a plan view of the aligner 54 and its periphery.

The structure of the aligner 54 is briefly described. As shown in FIG. 10( a), the aligner 54 comprises: a container member 92, a holding portion 93, a support portion 94, a motor 95 (a driving mechanism of the present invention), and a camera 96. The container member 92 is formed with an opening 92a. A holding portion 93 for holding a wafer W is arranged on the outer side of the container member 92. The support portion 94 supports the holding portion 93 from below. The motor 95 rotationally drives the support portion 94. The camera 96 photographs the outer edge of the wafer W that is rotating while being held by the holding portion 93. Thus, the aligner 54 measures the position of the wafer W that is held by the transport robot arm 3 and deviates from the target holding position, and sends the measurement result to the robot arm control unit 11.

The support part 94 is driven to rotate by the motor 95, and dust is generated in the container member 92. Therefore, as shown in FIG. 10(a), a nitrogen discharge port 97 is formed for the container member 92. The discharge port 97 is connected to a connection path 98a formed by a connection tube 98. As shown in FIG. 10(b), the connection path 98a connects the container member 92 and the return path 43. Furthermore, a fan 99 may be arranged for the connection path 98a.

(3) In the above-described embodiments, the spaces 21a to 24a formed inside the pillars 21 to 24 constitute the return path 43, but the present invention is not limited thereto. That is, the return path 43 may be formed by other components.

(4) In the above-mentioned embodiments, nitrogen is used as the inert gas, but the present invention is not limited to this. For example, argon or the like may be used as the inert gas.

1:EFEM 3:Transporter arm (automatic device) 12:Fan control unit (control unit) 43:Return path 44:FFU (fan filter unit) 54:Alignment device (automatic device) 61:Container component 61a:Opening 62:Support (support unit) 63:Drive mechanism 70:Arm mechanism (holding unit) 71,72,73:Arm component 71a,72a,73a:Internal space 71b,72b,73b:Inlet 71c,72c,73c:Outlet 74:Robot 77:Moving part (switching unit) 82a:Connection path 83:Fan 87:Ejector 92: container member 93: holding part 94: support part 95: motor (driving mechanism) 98a: connection path W: wafer (substrate)

[Fig. 1] is a schematic plan view of the EFEM and its periphery related to the present embodiment. [Fig. 2] is a diagram showing the electrical structure of the EFEM. [Fig. 3] is a front view of the frame. [Fig. 4] is a cross-sectional view taken along line IV-IV of Fig. 3. [Fig. 5] is a cross-sectional view taken along line V-V of Fig. 3. [Fig. 6] is a diagram showing the structure of the transport machine arm. [Fig. 7] is a schematic diagram showing the supply path and discharge path of nitrogen for the circulation path. [Fig. 8] is a diagram showing the delivery port of nitrogen in the transport machine arm. [Fig. 9] is a diagram showing the transport machine arm related to a modification. [Fig. 10] is a diagram showing an aligner related to another modification.

1:EFEM

2: Frame

3: Transport machine arm (automatic device)

4: Loading port

40: Circulation path

41:Transportation room

43: Return path

44: FFU (Fan Filter Unit)

46: Fan

61:Container component

61b: Send to the exit

70: Arm mechanism (holding part)

71,72,73: Arm components

74: Robotic Arm

79: Sleeve

81: Delivery Department

82: Connecting pipe

82a: Connection path

83: Fan

86: Attraction Department

87: ejector

87a: Nozzle

87b: Diffuser

87c: suction port

88a: Supply path

88b: Sending path

88c: Attraction path

91: Replace path

91a: Supply path

111: Supply source

115: Supply source

116: Supply source

Claims (6)

An EFEM comprises: a transfer chamber in which inactive gas purified by a fan filter unit for removing dust flows in a specific direction, and a container member disposed in the transfer chamber and having an opening, and a return path for returning the inactive gas to the fan filter unit from the downstream side of the transfer chamber in the specific direction, wherein the inactive gas is circulated in the EFEM, and the EFEM is characterized in that: a connection path is provided for connecting the container member and the return path; and a channel is provided in the return path for sending the ambient air in the return path to the front. The first fan on the downstream side of the specific direction; the connecting path is connected to the downstream side of the transfer chamber in the specific direction, and is connected to the return path on the upstream side of the first fan; the EFEM has: an automatic device configured in the transfer chamber to hold the substrate and perform specific actions; the automatic device has: the container member; the connecting path; a holding part configured outside the container member to hold the substrate; a supporting part that supports the holding part and is inserted into the opening; and a driving mechanism accommodated in the container member to drive the supporting part. The EFEM as described in claim 1 is further equipped with: The second fan for sending the ambient air in the aforementioned container component to the aforementioned return path through the aforementioned connecting path. The EFEM as described in claim 2 is further provided with: a fan driving device for rotationally driving the aforementioned second fan; and a control unit for controlling the aforementioned fan driving device; when the aforementioned driving mechanism is in operation, the aforementioned control unit adjusts the rotation speed of the aforementioned second fan to be faster than when the aforementioned driving mechanism is not in operation. An EFEM as recited in any one of claims 1 to 3, wherein a transporting machine arm for transporting the substrate is provided as the automatic device; the container member is fixed in the transport chamber; an arm mechanism for holding the substrate and transporting it in a horizontal direction is provided as the holding portion; a support for supporting the arm mechanism is provided as the supporting portion; and the support is driven up and down by the driving mechanism. The EFEM as described in claim 4, wherein the arm mechanism has a hollow arm member: the arm member has an inlet for allowing the inactive gas to flow into the internal space of the arm member, and an outlet for allowing the ambient gas to flow out from the internal space of the arm member. A gas replacement method for an EFEM, applied to an EFEM described in any one of claims 1 to 3, characterized in that: the inert gas is supplied from the inert gas supply source to the interior of the container component, and the inert gas is sent from the interior of the container component to the return path to replace the ambient air inside the container component; after the gas environment in the transfer chamber becomes less than a specific oxygen concentration, the supply of the inert gas from the supply source is stopped, and the ambient air in the transfer chamber is introduced into the interior of the container component and sent to the return path.

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