JP7125591B2 - Loadport and EFEM - Google Patents

Description

TECHNICAL FIELD The present invention relates to a load port functioning as an interface unit for transferring an object to be transported contained in a container to a transport space, and an EFEM provided with the load port.

For example, in a semiconductor manufacturing process, wafers are processed in a clean room in order to improve yield and quality. In recent years, a "mini-environment system" has been adopted to further improve the cleanliness of only the local space around the wafer, and a means of transporting the wafer and performing other processes has been adopted. In the mini-environment method, part of the wall surface of the wafer transfer chamber (hereinafter referred to as the transfer chamber), which is almost closed inside the housing, is formed, and objects to be transferred such as wafers are stored in the highly clean internal space. Adjacent to the transfer chamber, a load port is provided adjacent to the transfer chamber for placing a transfer container (hereinafter "container") and opening and closing a container door (hereinafter "container door"). Hereinafter, the door of the load port that can be engaged with the container door to open and close the container door will be referred to as "load port door".

The load port is a device for loading and unloading objects to be transported into and out of the transport chamber, and functions as an interface between the transport chamber and a container (for example, a FOUP (Front-Opening Unified Pod)). Then, when the FOUP door and the load port door are opened at the same time with the load port door facing the FOUP door (hereinafter referred to as "FOUP door") with a predetermined gap, the transfer robot arranged in the transfer chamber is opened. (Wafer transfer device) is configured to take out the object to be transferred from the FOUP into the transfer chamber, or to store the object to be transferred from the transfer chamber into the FOUP.

In order to properly maintain the atmosphere around the wafers, a sealed storage pod called a FOUP is used as a container, and the wafers are accommodated and managed inside the FOUP. Furthermore, an EFEM (Equipment Front End Module) comprising a transfer chamber and a load port is used to transfer wafers between the processing equipment that processes the wafers and the FOUPs.

In recent years, high integration of devices and miniaturization of circuits have progressed, and it is required to maintain a high degree of cleanliness around the wafer so that particles and moisture do not adhere to the wafer surface. Therefore, in order to prevent the surface property of the wafer from being oxidized or otherwise changed, the inside of the FOUP is filled with nitrogen to create a nitrogen atmosphere, which is an inert gas, or to create a vacuum around the wafer. It is

Furthermore, in the cutting-edge wafer process, even oxygen and moisture contained in the clean atmosphere used as a constant downflow from the fan filter unit located at the top of the transfer chamber may change the properties of the wafer. Therefore, there is a demand for practical application of a technique for circulating an inert gas in an EFEM, as in Patent Document 1. The system described in Patent Literature 1 has a configuration in which a seal member is provided at an appropriate location in the load port so as to form a sealed space between the container door (FOUP door) and the load port door.

However, with the above configuration in which the sealing member is provided, air and particles remain in the sealed space, and the FOUP door and the load port face each other with the load port door facing the FOUP door with a predetermined gap. When the doors are opened at the same time, air and particles remaining in the closed space enter the FOUP and transfer chamber, which may change the properties of wafers in EFEM, which requires low oxygen concentration and low humidity. could be.

Therefore, the applicant removes the atmosphere from the closed space by using a gas injection nozzle for injecting gas into the closed space between the FOUP door and the load port door and a gas discharge nozzle for discharging the gas in the closed space. Then, a configuration for filling (purging) nitrogen gas was devised (Patent Document 2). In this way, by replacing the gas in the closed space formed between the FOUP door and the load port door with nitrogen (hereinafter referred to as door purge), particles adhering to the FOUP door will be removed from the EFEM transfer chamber when the door is opened. and to prevent oxygen contained in the minute space between the FOUP door and the load port from flowing into the EFEM transfer chamber.

JP 2014-112631 A International publication 2017/022431

However, in order to shorten the tact time, the time required for door purge (nitrogen replacement processing of the closed space) is limited. Therefore, if the amount of nitrogen gas supplied to the sealed space is increased, the pressure in the sealed space increases. If the closing force of the load port door is insufficient, the load port door side cannot be sealed, and gas containing oxygen and particles in the closed space may flow into the EFEM transfer chamber. It can happen.

On the other hand, in order to avoid the occurrence of such a situation, it is conceivable to adopt a configuration in which the gas atmosphere in the closed space is sucked. The closed space becomes negative pressure. As a result, it is conceivable that the FOUP door will be pulled toward the sealed space, and the tightness with respect to the container body will deteriorate, causing the gas in the FOUP to flow into the sealed space. At the bottom of the FOUP, a nitrogen gas supply port for purging the inside of the FOUP (bottom purge processing) and an exhaust port for naturally discharging gas from the FOUP are provided. If is larger than the gas supply amount, gas (atmosphere) may be sucked into the FOUP from the exhaust port for bottom purge processing, flow back, and flow into the closed space and eventually into the EFEM transfer chamber.

The present invention has been made with a focus on such problems, and the main purpose is to shorten the time required for door purge processing or closed space cleaning processing according to door purge processing, and to transport objects ( It is an object of the present invention to provide a load port having a structure that does not allow undesired gas, which may cause changes in the properties of wafers, to flow into the transfer chamber, and an EFEM equipped with such a load port. The present invention is a technique applicable to load ports and EFEMs that can handle containers other than FOUPs.

That is, the present invention comprises a base that constitutes part of a wall that separates a transfer space from an external space and that has an opening through which an object to be transferred can pass, and a container door of a container containing the object to be transferred. a load port door capable of opening and closing the opening of the base; a first sealing portion that seals between the base and a container arranged at a predetermined position in front of the base; and a closed state that closes the opening. and a second seal portion for sealing between the load port door and the base, and when the load port door is closed and the container is in contact with the base via the first seal portion, the load The basic configuration of the load port is such that the space in which the port door and the container door are opposed to each other with a gap of a predetermined size is divided by a first seal portion and a second seal portion to form a sealed space.

In addition, the load port according to the present invention, in such a basic configuration, further includes a gas injection section for injecting gas into the sealed space, and part or all of the first seal section is used to fill the sealed space during door purge processing. It is characterized in that it is set as a priority opening portion that is opened with priority over the second seal portion by applying a positive pressure, and at least the gas in the closed space can be exhausted through this opened portion.

Here, in the present invention, the portion that is opened with priority over the second seal portion when the sealed space is in the positive pressure state may be a part of the first seal portion or the first seal portion. may be all of In other words, it has been conceived so far to set at least one portion of the first seal portion at which the sealed state is released (a portion that is easily exhausted) when the sealed space is in a positive pressure state. This configuration is unique to the present invention. Further, the present invention provides a configuration in which the priority opening portion of the first seal portion is opened with priority over the second seal portion at the time when the sealed space becomes positive pressure, and the sealed space becomes positive pressure. At an appropriate time (for example, when the pressure in the sealed space reaches a predetermined value or more) after that time, the preferentially opened portion of the first seal portion is opened with priority over the second seal portion. configuration, including both of these configurations.

The load port according to the present invention has a door purge function capable of replacing the sealed space between the container door and the load port door and sealed by the first seal portion and the second seal portion with gas by the gas injection portion. Therefore, particles adhering to the container door, or existing between the container door and the load port door to oxidize the wafer, such as oxygen, moisture, which may change the wafer properties It is possible to prevent or suppress a situation in which air containing particles or the like flows into the transfer space and the inside of the container when the load port door is opened. That is, before the container door is opened to open the sealed space, oxygen, moisture, and particles in the sealed space can be removed.

Further, in the load port according to the present invention, the sealed space is set to a positive pressure during door purge processing, so that the priority opening portion set in part or all of the first seal portion is opened with priority over the second seal portion, At least the gas in the closed space (which may include air, particles, etc. existing in the closed space before the door purge process is executed) can be exhausted through this open portion, so the closed space becomes a positive pressure. Due to this, the closing force of the load port door is weakened, and particles adhering to the container door, oxygen, moisture, particles, etc. existing between the container door and the load port door before the door purge process is executed. It is possible to prevent the atmosphere containing the air from flowing into the transfer space from the sealed space. As a result, the cleanliness of the inside of the container, the sealed space, and the transfer space can be maintained, and a large amount of gas can be supplied to the sealed space in a short time to keep the sealed space in a positive pressure state. The tact time can be shortened compared to the mode in which the dust and the like in the closed space is removed while the pressure is adjusted by supplying the gas little by little.

In addition, with the load port of the present invention, there is no need for special control such as equalizing the pressure in the closed space with the pressure in other spaces, and there is no need for control equipment (valves and piping) for control. It is possible to reduce costs and shorten takt time by increasing the number of parts.

In particular, if the load port according to the present invention is provided with a gas discharge section for discharging gas from the sealed space, it is difficult to replace the gas in the sealed space compared to a configuration that does not have a gas discharge section. It is possible to prevent and suppress situations that may occur. In addition, if such a load port adopts a configuration in which an exhaust unit is provided under atmospheric pressure near the preferential opening portion and outside the sealed space, when the pressure in the sealed space increases, The exhaust unit can efficiently exhaust at least gas such as the door purge gas that leaks out of the sealed space from the priority opening portion set in the first seal portion, which is the sealing member on the container side.

In addition to the basic configuration described above, the load port according to the present invention has a configuration in which a discharge portion for discharging gas from the sealed space is provided. It is characterized in that it is set as a priority opening portion that is opened with priority over the first seal portion by making the sealed space negative pressure during the sealed space cleaning process.

Here, in the present invention, the portion that is opened preferentially over the first seal portion when the sealed space is in the negative pressure state may be a part of the second seal portion or the second seal portion. may be all of In other words, it has been conceived so far to set at least one portion of the second seal portion where the sealed state is released (a portion that is easily exhausted) when the sealed space is in a negative pressure state. This configuration is unique to the present invention. Further, the present invention provides a configuration in which the priority opening portion of the second seal portion is opened with priority over the first seal portion at the time when the sealed space becomes negative pressure, or the sealed space becomes negative pressure. At an appropriate time (for example, when the pressure in the closed space becomes equal to or less than a predetermined value) after that time, the priority opening portion of the second seal portion is opened with priority over the first seal portion. configuration, including both of these configurations.

The load port according to the present invention exerts a function of exhausting and cleaning the sealed space between the container door and the load port door and sealed by the first seal portion and the second seal portion by the discharge portion. Therefore, particles adhering to the container door, and oxygen, moisture, particles, etc. that may change the properties of the wafer, such as those existing between the container door and the load port door, oxidizing the wafer. can be prevented/suppressed from flowing into the transfer space and the inside of the container when the load port door is opened. That is, before the container door is opened to open the sealed space, oxygen, moisture, and particles in the sealed space can be removed.

Further, in the load port according to the present invention, in order to shorten the takt time, when a large amount of air is exhausted from the sealed space to the outside of the sealed space in a short time to put the sealed space in a negative pressure state, one part of the second seal portion The priority open portion set to the first seal portion or all of the first seal portions is opened with priority over the first seal portion, and gas flows from the transfer space into the sealed space through this open portion, resulting in a negative pressure in the sealed space. As a result, the closing force of the container door weakens, and the particles adhering to the container door and the oxygen present between the container door and the load port door at the time before the cleaning process of the sealed space using the discharge unit is performed. Air containing , moisture, particles, etc. flows into the container from the sealed space, or the sealed space becomes negative pressure. An air current is formed from the inside toward the sealed space, and it is possible to completely prevent a situation in which the gas (atmosphere) flows back into the container or the sealed space from the exhaust port at the bottom of the container. As a result, it is possible to maintain a high degree of cleanliness in the container, the sealed space, and the transfer space, and it is also possible to exhaust a large amount of air into the sealed space in a short period of time to create a negative pressure in the sealed space. The tact time can be shortened compared to the mode in which dust and the like are removed from the sealed space while the pressure is adjusted by exhausting the air.

In addition, with the load port of the present invention, there is no need for special control such as equalizing the pressure in the closed space with the pressure in other spaces, and there is no need for control equipment (valves and piping) for control. It is possible to reduce costs and shorten takt time by increasing the number of parts.

In particular, if the load port according to the present invention is provided with a gas injection part for injecting gas into the sealed space, it exerts a door purge function of replacing the inside of the sealed space with gas, and during the door purge process, the inside of the sealed space is filled with gas. It is possible to prevent and suppress a situation in which a place where gas is difficult to replace can occur. In addition, in the load port according to the present invention, by adopting a configuration in which an exhaust unit is provided at a predetermined position of the suction path for sucking the inside of the sealed space, when the sealed space becomes a negative pressure state, the gas in the sealed space (In the case of a configuration with a gas injection part, including door purge gas) can be efficiently exhausted outside the closed space by the exhaust unit, and a situation that can occur if an excessive negative pressure state occurs, that is, due to the container door It is also possible to solve the problem that the degree of airtightness in the container is lowered and the air flows back into the container from the exhaust port provided in the container.

Further, the EFEM according to the present invention is characterized by comprising a load port having the above configuration and a transfer chamber in which a transfer robot is arranged in the transfer space. With such an EFEM, it is possible to transfer objects such as wafers between the container set on the load port and the transfer chamber by the transfer robot. By adopting a configuration in which the priority opening part is opened by applying positive or negative pressure to the closed space when performing space cleaning processing, the gas in the closed space (door purge gas) can be released outside the closed space through the open part. or gas can flow from the transfer space to the sealed space through the open portion, and the loading and unloading process can be performed while maintaining high cleanliness in the container, the sealed space, and the transfer space. In particular, in the EFEM according to the present invention, if the transfer chamber has a circulation duct for circulating gas in the transfer space, a predetermined gas (for example, an inert gas or an environmental gas such as nitrogen gas) is introduced into the transfer space. It can be circulated and kept clean. In this case, the differential pressure of the transfer space with respect to the external space (under atmospheric pressure) outside the transfer space is preferably plus 3 to 500 Pa (G).

According to the present invention, the gap between the container door and the load port door of the container arranged at a predetermined position in front of the base is doubled by the first seal portion and the second seal portion in the front-rear direction where these doors face each other. The sealing structure is set in a sealed space, configured to generate a pressure difference between the pressure in the sealed space and the atmospheric pressure, and in a state in which the pressure difference is generated, either the first seal portion or the second seal portion is closed. Since it is set so that part or all of it is opened preferentially, it is possible to shorten the time required for door purge processing or closed space cleaning processing, while preventing changes in the properties of the objects to be transported (wafers, etc.). It is possible to provide a load port and an EFEM with such a load port that do not allow unwanted gases to enter the transfer chamber.

1 is a schematic side view showing the relative positional relationship between an EFEM having a load port and its peripheral devices according to an embodiment of the present invention; FIG. FIG. 2 is a perspective view showing a partially omitted load port according to the embodiment; The x direction arrow directional view of FIG. y-direction arrow view of FIG. FIG. 4 is a diagram schematically showing a side cross section of the load port according to the embodiment with the container separated from the frame and the load port door in the fully closed position; FIG. 6 is a view corresponding to FIG. 5 and showing a state in which the container is in contact with the frame via the first seal portion and the load port door is in the fully closed position; FIG. 6 is a view corresponding to FIG. 5 and showing a state where the load port door is in the open position; The whole window unit perspective view in the same embodiment. FIG. 7 is an enlarged view of a main portion of FIG. 6 and schematically showing a point in time when a sealed state is maintained by a first seal portion and a second seal portion; FIG. 10 is a view corresponding to FIG. 9 and showing a point in time when the sealed state by the first seal portion is released in the same embodiment; FIG. 10 is a diagram showing a main part of a load port according to a second embodiment of the invention, corresponding to FIG. 9; FIG. 12 is a view corresponding to FIG. 11 and showing a point in time when the sealed state by the second seal portion is released in the same embodiment;

An embodiment of the present invention will be described below with reference to the drawings.

The load port 2 according to the present embodiment is used, for example, in a semiconductor manufacturing process, and as shown in FIG. It is for taking in and out objects to be conveyed between them. In the following description, a load port 2 constituting a part of an EFEM (Equipment Front End Module) according to the present invention transports an object to be transported, for example, a wafer W, together with a container 4 (for example, a FOUP in this embodiment). A description will be given of a manner in which wafers are loaded and unloaded between chambers 3 (wafer transfer chambers). The size of the wafer handled by EFEM is standardized as the SEMI (Semiconductor Equipment and Materials International) standard, but from the viewpoint of improving productivity, the diameter of the wafer has been increased, and the diameter has been increased from 300 mm to 450 mm. A move to 500 mm wafers is being driven.

In the following description, in the front-rear direction D in which the FOUP 4, the load port 2, and the transfer chamber 3 are arranged in this order, the transfer chamber 3 side is defined as "rear" and the FOUP 4 side is defined as "front". A direction perpendicular to the vertical direction H is defined as "lateral". Therefore, in this embodiment, the wall surface 3A of the transfer chamber 3 on which the load port 2 is arranged can be regarded as the front wall surface.
As shown in FIGS. 1, 5 and 9, the FOUP 4 in this embodiment includes a FOUP body 42 which can open the internal space 4S only rearward through a loading/unloading port 41 formed in the rear surface 42B (the surface on the side of the base 21). , and a FOUP door 43 (corresponding to the “container door” of the present invention) capable of opening and closing the loading/unloading port 41 . The FOUP 4 is a known FOUP 4 that accommodates a plurality of wafers W, which are objects to be transferred, in a multistage manner in the vertical direction H, and is configured such that these wafers W can be taken in and out through a loading/unloading port 41 .

The FOUP body 42 integrally has a front wall, a pair of left and right side walls, a top wall and a bottom wall. The inner space 4S surrounded by these walls is provided with a shelf (wafer placing portion) on which wafers W can be placed on a plurality of stages at a predetermined pitch. A flange portion that is gripped by a container transport device (for example, OHT: Over Head Transport) is provided at the center of the upward surface of the upper wall. A rear end portion of the FOUP main body 42 is provided with a flange portion 45 that protrudes upward and to both sides more than other portions. In other words, the flange portion 45 is provided around the area of the FOUP body 42 where the FOUP door 43 is arranged.

The FOUP door 43 faces the load port door 22 of the load port 2 when mounted on a mounting table 23 (described later) of the load port 2, and has a substantially plate shape. The height dimension of the FOUP door 43 is set substantially equal to the height dimension of the surface of the load port door 22 that faces the FOUP door 43 with a predetermined gap therebetween. 5 and the like schematically show the FOUP door 43 whose height dimension is set to be slightly larger than the height dimension of the surface of the load port door 22 facing the FOUP door 43 with a predetermined gap therebetween. ing. The FOUP door 43 is provided with a latch portion (not shown) capable of locking the FOUP door 43 to the FOUP body 42 . A gasket (not shown) is provided on a predetermined portion of the inward surface 431 of the FOUP door 43 that contacts or approaches the FOUP main body 42 when the loading/unloading port 41 is closed by the FOUP door 43 . By bringing the gasket into contact with the FOUP main body 42 prior to the inward facing surface 431 of the FOUP door 43 and elastically deforming it, the inner space 4S of the FOUP 4 can be sealed.

The load port 2 according to this embodiment, as shown in FIGS. , a load port door 22 for opening and closing an opening 21a of the base 21, and a mounting table 23 provided on the base 21 in a substantially horizontal posture. Here, the opening 21a for opening the internal space 3S of the transfer chamber 3 is an opening formed in the base 21 for opening the internal space 3S of the transfer chamber 3, which is a space partitioned by the base 21. FIG.

The base 21 is arranged in an upright posture and has an approximately rectangular plate shape with an opening 21a large enough to communicate with the loading/unloading port 41 of the FOUP 4 placed on the mounting table 23 . The load port 2 of this embodiment can be used with the base 21 in close contact with the transfer chamber 3 . A leg portion 24 having casters and installation legs is provided at the lower end of the base 21 . In this embodiment, columns 211 erected on both sides, a base body 212 supported by the columns 211, and a window unit 214 attached to a substantially rectangular window 213 opened in the base body 212 are provided. A base 21 is applied.

The window unit 214 is provided at a position facing the FOUP door 43, and the opening 215 provided in this window unit 214 corresponds to the "opening through which the object to be conveyed" in the present invention.

Here, the term "substantially rectangular" as used in the present embodiment refers to a shape in which the four corners are smoothly connected by arcs while the basic shape is a rectangle having four sides. Although not shown, a rectangular frame-shaped gasket as an elastic material is provided in the vicinity of the outer periphery of the surface (front surface) of the base body 212 on the transfer chamber 3 side, and the base 21 of the transfer chamber 3 is provided with a gasket. The gap between the base body 212 and the transfer chamber 3 is eliminated by bringing the gasket into contact with the vicinity of the edge of the opening where the GS is mounted, so that the internal space 3S of the transfer chamber 3 passes through the gap between the base body 212 and the transfer chamber 3 to the external GS. It is designed to prevent gas leakage to the

The mounting table 23 of the load port 2 is provided on top of a horizontal base 25 (support base) that is arranged in a substantially horizontal position at a position slightly above the center in the height direction of the base 21 . The mounting table 23 can mount the FOUP 4 in such a direction that the FOUP door 43 for opening and closing the internal space 4S of the FOUP main body 42 faces the load port door 22 . 5 and 6, the mounting table 23 has a predetermined docking position (see FIG. 6) where the FOUP door 43 approaches the opening 21a of the base 21, and a position where the FOUP door 43 is located closer to the base than the docking position. 21 and a position separated by a predetermined distance (see FIG. 5). As shown in FIG. 2, the mounting table 23 has a plurality of protrusions (pins) 231 protruding upward. , the positioning of the FOUP 4 on the mounting table 23 is attempted. 5 and 6 show a state in which the bottom surface of the FOUP 4 is in contact with the top surface of the mounting table 23 as the mounting state of the FOUP 4 on the mounting table 23. FIG. However, in reality, a plurality of positioning projections 231 protruding above the upper surface of the mounting table 23 engage with bottomed holes formed in the bottom surface of the FOUP 4 to support the FOUP 4. The top surface of the mounting table 23 and the bottom surface of the FOUP 4 do not contact each other, and a predetermined gap is formed between the top surface of the mounting table 23 and the bottom surface of the FOUP 4 . Further, lock claws 232 are provided for fixing the FOUP 4 to the mounting table 23 . By hooking the locking claws 232 to a locked portion (not shown) provided on the bottom surface of the FOUP 4 and fixing it in a locked state, the FOUP 4 can be positioned properly on the mounting table 23 in cooperation with the positioning projections 231 . It can be fixed while guiding to. Further, the FOUP 4 can be separated from the mounting table 23 by releasing the locked state of the lock claw 232 with respect to the locked portion provided on the bottom surface of the FOUP 4 .

The load port 2 of this embodiment has a plurality of nozzles 261 at predetermined locations on the mounting table 23 . These nozzles 261 flow into the FOUP 4 from the bottom side of the FOUP 4 with an environmental gas (also called purge gas, nitrogen gas or dry air is mainly used) which is an appropriately selected gas such as nitrogen gas, inert gas, or dry air. is injected to replace the gas atmosphere in the FOUP 4 with the environmental gas. These nozzles 261 function as bottom purge injection nozzles for injecting environmental gas into the FOUP 4 and bottom purge discharge nozzles for discharging the gas atmosphere inside the FOUP 4. They can be provided in pairs at spaced apart positions. The plurality of nozzles 261 can be connected while being fitted to an inlet and an outlet (both not shown) provided at the bottom of the FOUP 4 . Each nozzle 261 (bottom purge injection nozzle, bottom purge discharge nozzle) or an injection port and a discharge port has a valve function to regulate backflow of gas. A fitting portion between each nozzle 261 (bottom purge injection nozzle, bottom purge discharge nozzle) and the injection port and discharge port of the FOUP 4 is sealed by a packing or the like provided on the nozzle 261 . In the load port 2 of the present embodiment, when the FOUP 4 is not placed on the mounting table 23 , each nozzle 261 (bottom purge injection nozzle, bottom purge discharging nozzle) is positioned higher than the upper surface of the mounting table 23 . positioned below. When it is detected that the bottom portion of the FOUP 4 presses the pressed portion of, for example, a pressure sensor provided on the mounting table 23, each nozzle 261 (bottom purge injection nozzle, bottom purge FOUP 4 is constructed so that the ejection nozzle) is advanced upward and connected to the injection port and the ejection port of the FOUP 4, respectively.

The load port door 22 connects the load port door 22 to the FOUP door 43, and releases the lid connection state in which the FOUP door 43 can be removed from the FOUP body 42, the connection state with respect to the FOUP door 43, and the FOUP door 43. is attached to the FOUP main body 42, and a connection mechanism 221 (see FIG. 4) is provided which can be switched between a state in which the lid is disconnected. The load port door 22 can be moved along a predetermined movement path while being held integrally with the FOUP door 43 by the connecting mechanism 221 . As shown in FIGS. 5 and 6, the load port 2 of the present embodiment is in a fully closed position in which the load port door 22 is held by the FOUP door 43 and the internal space 4S of the FOUP body 42 is sealed. (C) and an open position (O) in which the FOUP door 43 held by the load port door 22 is separated from the FOUP main body 42 and the internal space 4S of the FOUP main body 42 is opened toward the transfer chamber 3. It is configured to be at least movable with The load port 2 of this embodiment can be moved to the open position (O) shown in FIG. 7 while maintaining the upright posture of the load port door 22 positioned at the fully closed position (C) shown in FIGS. Further, it is configured to be movable downward from the open position (O) shown in FIG. 7 to the fully open position (not shown) while maintaining the standing posture. That is, the movement path of the load port door 22 between the fully closed position (C) and the fully open position is such that the load port door 22 at the fully closed position (C) is moved to the open position (O) while maintaining its height position. and a path (vertical path) along which the load port door 22 in the open position (O) is moved downward while maintaining its longitudinal position. At the open position (O) where the path and the vertical path intersect, the moving direction of the load port door 22 switches from the horizontal direction to the vertical direction, or from the vertical direction to the horizontal direction. The FOUP door 43 held by the load port door 22 positioned in the open position (O) can move in both vertical and horizontal directions. Together with the door 22, it is positioned behind the base 21 (a position completely separated from the FOUP main body 42 and arranged in the internal space 3S of the transfer chamber 3).

Such movement of the load port door 22 is realized by a door moving mechanism 27 provided in the load port 2 . As shown in FIGS. 5 to 7, the door moving mechanism 27 includes a support frame 271 that supports the load port door 22, and a movable block that supports the support frame 271 movably in the front-rear direction D via slide support portions 272. 273, slide rails 274 that support the movable block 273 so as to be movable in the vertical direction H, and movement of the load port door 22 in the front-rear direction D along the horizontal path and in the vertical direction H along the vertical path. and a drive source (for example, an actuator (not shown)) for By giving a drive command from the controller 2C to this actuator, the load port door 22 can be moved in the front-back direction D and the up-down direction H. An actuator for front-rear movement and an actuator for vertical movement may be provided separately, or a common actuator may be used as a drive source for front-rear movement and vertical movement.

The support frame 271 supports the lower rear portion of the load port door 22 . The support frame 271 has a substantially crank-like shape extending downward, passing through a slit-shaped insertion hole 21b formed in the base 21, and protruding to the outside of the transfer chamber 3 (toward the mounting table 23 side). be. In this embodiment, a slide support portion 272 , a movable block 273 and a slide rail 274 for supporting the support frame 271 are arranged outside the transfer chamber 3 . These slide support portion 272 , movable block 273 , and slide rail 274 serve as sliding portions when the load port door 22 is moved. In this embodiment, by arranging these outside the transfer chamber 3, even if particles are generated when the load port door 22 is moved, the insertion hole 21b is set in a minute slit shape. Therefore, it is possible to prevent or suppress the entry of particles into the transfer chamber 3 . In addition, a cover 28 that covers the parts and portions of the door moving mechanism 27 that are arranged outside the transfer chamber 3, specifically, a part of the support frame 271, the slide support portion 272, the movable block 273, and the slide rail 274. is provided. As a result, the environment gas in the transfer chamber 3 is set so as not to flow out to the outside GS of the EFEM 1 through the insertion hole 21 b formed in the base 21 .

As shown in FIGS. 5 and 9, the load port 2 according to the present embodiment includes a first seal portion 5 and a second seal portion 6 provided near the periphery of the opening 21a. is closed and the FOUP door 43 is in contact with the base 21 via the first seal portion 5, the FOUP door 43 and the load port door 22 face each other with a predetermined gap in the front-rear direction D. The space is separated from the outside GS by the first seal portion 5 and the second seal portion 6 to form a closed space DS. In this embodiment, the first seal portion 5 and the second seal portion 6 are unitized as the window unit 214 described above.

As shown in FIGS. 2 to 4 and 8, the window unit 214 has a substantially rectangular opening 215 at a position facing the FOUP door 43 in the window unit 214 (the central portion of the window unit 214 in the illustrated example). It is composed mainly of a frame-shaped window frame portion 216 having a

In this embodiment, the opening 215 of the window frame 216 is set to be slightly larger than the outer circumference (outer dimension) of the FOUP door 43, and the FOUP door 43 is held by the load port door 22 through this opening 215. It is constructed so that it can be moved into the transfer chamber 3 in a state where it is held. The opening 215 of the window frame 216 is the opening 21a of the base 21 itself.

The first seal portion 5 is provided so as to surround the opening 21a in the vicinity of the opening edge of the opening 21a on the front surface of the base 21, and when the mounting table 23 on which the FOUP 4 is mounted is positioned at the docking position, It seals between the periphery of the opening 21a of the base 21 and the FOUP 4 (see FIGS. 6 and 9). In this embodiment, which employs a configuration in which the window unit 214 is attached to the base 21, the first seal portion is positioned around the opening 215 in the region near the opening edge of the opening 215 on the front surface 216A of the window frame portion 216. 5 is provided (see FIG. 8). Specifically, in the front surface 216A of the window frame portion 216, the first seal surface (the surface of the FOUP body 42 set around the FOUP door 43), which is the rear surface 42B of the FOUP body 42, is opposed to the first sealing surface. The seal part 5 is made to go around and attached. The first seal portion 5 arranged so as to surround the rectangular opening 215 near the edge of the opening 215 has a substantially rectangular shape when viewed from the FOUP 4 side. Therefore, as shown in FIG. 8, the first seal portion 5 includes an upper side portion 5A arranged near the upper edge of the opening 215, a lower side portion 5B arranged near the lower edge of the opening 215, It can be roughly divided into side portions 5</b>C arranged near both side edges of the opening 215 . The first seal portion 5 of this embodiment, which has a basic shape of a rectangle having these four side portions 5A, 5B, and 5C, has a shape in which the four corners are smoothly connected by circular arcs.

In this embodiment, as shown in FIG. 9, most of the first seal portion 5 is formed of an elastic body (circular elastic body D1) having a substantially circular cross-sectional shape, and a part is formed of an elastic body having a substantially circular cross-sectional shape. It is formed of an elastic body (non-circular elastic body D2) that is more elastically deformable than the elastic body. Specifically, predetermined portions including the entire lower side portion 5B, the entire left and right side portions 5C, and both width direction end portions of the upper side portion 5A of the first seal portion 5 are formed of the circular elastic body D1, and the first seal portion 5, the central portion in the width direction of the upper side portion 5A is formed of a non-circular elastic body D2. The non-circular elastic body D2 of the present embodiment has a rod-shaped cross section (a rod shape whose longitudinal dimension in the cross-sectional view is larger than the diameter of the substantially circular elastic body), and has a rounded tip that extends forward. It is an elastic body arranged in a posture of gradually displacing upward (a posture of jumping up, a posture in which the tip portion is displaced in a direction toward the outside of the closed space DS GS). 5 to 8 schematically show the first seal portion 5 without clearly distinguishing between the circular elastic body D1 and the non-circular elastic body D2.

Such a first sealing portion 5 exerts a sealing function by being interposed between the peripheral edge of the opening 21a of the base 21 and the FOUP 4 when the mounting table 23 on which the FOUP 4 is mounted is positioned at the docking position. In a state where the sealing function is exhibited, the differential pressure between the sealed space DS including the sealed area by the first seal portion 5 and the external GS (under atmospheric pressure) is, for example, 500 Pa (G) or less, preferably 300 Pa (G) or less. 10, the portion of the first seal portion 5 formed of the non-circular elastic body D2 is released and opened prior to the portion formed of the circular elastic body D1. . Hereinafter, the portion of the first seal portion 5 formed of the non-circular elastic body D2 is referred to as a preferential opening portion X, and the portion formed of the circular elastic body D1 is referred to as a non-opening portion Y.

FIG. 9 shows a state in which the first seal portion 5 (both the priority opening portion X and the non-opening portion Y) is in elastic contact with the FOUP 4 mounted on the mounting table 23 positioned at the predetermined docking position. is shown. In the load port 2 of the present embodiment, the first seal portion 5 is arranged in a form in which the first seal portion 5 protrudes from the end surface of the load port door 22 closest to the FOUP 4 toward the FOUP 4 by a predetermined dimension L2 (for example, 0.1 mm or more and 3 mm or less). is doing. Therefore, the FOUP door 43 and the load port door 22 do not come into contact with each other, and the high sealing performance of the sealed space DS formed between the base 21 and the load port door 22 can be maintained by the first seal portion 5 . .

That is, as shown in FIG. 9, the first seal portion 5 is in elastic contact with the rear surface 42B of the FOUP main body 42 mounted on the mounting table 23 positioned at the predetermined docking position. In particular, the preferential opening portion X of the first seal portion 5 is elastically contacted with the FOUP 4, so that the tip portion is pushed upward (in the direction toward the outside of the sealed space DS GS) than before the elastic contact with the FOUP 4. elastically deformed. The non-open portion Y of the first seal portion 5 elastically contacts the FOUP 4 by elastically contacting the rear surface 42B of the FOUP main body 42 mounted on the mounting table 23 positioned at the predetermined docking position. It is elastically deformed into a shape more crushed in the front-rear direction D than at the previous time. By maintaining such an elastic contact state between the first seal portion 5 and the FOUP 4, a good seal area can be formed.

In FIGS. 5 to 7, the first seal portion 5 and the second seal portion 6 are schematically shown by substantially elliptical marks filled in black. 6 and 7, the rear surface 42B (seal surface) of the FOUP body 42 is in contact with the base 21 (window unit 214). 214), and as described above, the first seal portion 5 is interposed between the seal surface of the FOUP body 42 and the base 21 (window unit 214).

The second seal portion 6 is provided on the rear surface 21B of the base 21 so as to surround the opening 21a in a region near the edge of the opening 21a. In this embodiment, which employs a configuration in which the window unit 214 is attached to the base 21, the second seal portion is provided at a position surrounding the opening portion 215 in the region near the opening edge of the opening portion 215 on the rear surface 216B of the window frame portion 216. 6 is provided. Specifically, of the rear surface 216B of the window frame portion 216, it faces the front surface of the load port door 22, that is, the seal surface set in a predetermined portion of the entire surface 21A of the base (the surface set in the outer edge portion of the load port door 22). The second seal portion 6 is mounted around the position where it is located. In this embodiment, a brim-shaped thin portion is formed on the outer edge portion of the load port door 22 , and this thin portion is set as the sealing surface of the load port door 22 . The second seal portion 6 arranged so as to surround the opening 215 in the vicinity of the opening edge of the rectangular opening 215 has a substantially rectangular shape when viewed from the transfer chamber 3 side.

In this embodiment, an O-ring having a substantially circular cross-sectional shape is applied as the second seal portion 6, and a common O-ring is applied to the upper side portion 6A, the lower side portion 6B, and the left and right side portions 6C of the second seal portion 6. are placed across. As described above, in the present embodiment, the entire second seal portion 6 is formed of an elastic body (circular elastic body D1) having a substantially circular cross-sectional shape, and the entire second seal portion 6 serves as the "unopened portion Y". have set. Then, when the load port door 22 is positioned at the closed position, the load port door 22 (more specifically, the thin portion) contacts the rear surface 216B of the window frame portion 216 via the second seal portion 6. As a result, the second seal portion 6 seals between the peripheral edge of the opening 21a of the base 21 and the load port door 22 (see FIG. 9). As a result, when the load port door 22 is positioned at the closed position, gas flows out from the internal space 3S of the transfer chamber 3 to the outside of the transfer chamber 3, or from the outside of the transfer chamber 3 to the internal space 3S of the transfer chamber 3. of gas can be suppressed. The central portion of the load port door 22, excluding the thin portion, is a thick portion that is thicker than the thin portion. 215) to face the opening 21a (opening 215).

In the load port 2 of the present embodiment, the front surface 216A and the rear surface 216B of the window frame portion 216 are provided with mounting grooves each having a concave shape in cross section so as to surround the vicinity of the opening edge of the opening portion 215 (the second groove in FIGS. 9 and 10). A concave portion in which the first seal portion 5 and the second seal portion 6 are fitted is formed. The first seal portion 5 and the second seal portion 6 are inserted into the respective seal mounting grooves and tightly mounted. In particular, the seal mounting groove in which the preferential opening portion X of the first seal portion 5 is attached is set to have a trapezoidal cross section that gradually widens toward the depth of the groove, and the base of the preferential opening portion X is set in this trapezoidal seal mounting groove. It is fixed by an appropriate means such as an adhesive agent in a state where the insertion portion provided at the end is fitted. This prevents the preferential release portion X of the first seal portion 5 from slipping out of the seal mounting groove. In this attached state, portions of the first seal portion 5 and the second seal portion 6 that are not accommodated in the attachment groove are exposed outside the attachment groove.

In addition, the load port 2 of this embodiment includes a movement restricting portion L that restricts movement of the FOUP 4 on the mounting table 23 positioned at the docking position in a direction (rearward) away from the base 21 . In this embodiment, the movement restricting portion L is unitized as a window unit 214 .

The movement regulating portion L regulates movement of the FOUP 4 on the mounting table 23 positioned at the docking position in a direction (rearward) away from the base 21, and the FOUP 4 on the mounting table 23 positioned at the docking position. can be switched between a movement-permitting state that permits movement in a direction away from the base 21 . That is, the movement restricting part L can hold the FOUP 4 placed on the placing table 23 positioned at the predetermined docking position by entering the movement restricting state.

As shown in FIG. 8 and the like, the movement restricting portion L in this embodiment includes an engaging piece L1 that can be engaged with a flange portion 45 provided around the FOUP door 43 of the FOUP body 42, and an engaging piece L1. A retracting portion L2 is provided for moving the L1 to the base 21 side while the L1 is engaged with the flange portion 45. - 特許庁Such a movement restricting portion L exerts a clamping function capable of holding the collar portion 45 of the FOUP body 42 in a state of being sandwiched between the engaging piece L1 and the base 21. As shown in FIG. In this embodiment, a window unit 214 is provided on the base 21 . Therefore, the movement restricting portion L has a function of sandwiching the collar portion 45 of the FOUP body 42 between the engagement piece L1 and the window frame portion 216 of the window unit 214 .

The engaging piece L1 can change its attitude between a non-facing attitude in which the entire engaging piece L1 including the tip does not face the FOUP 4 in the front-rear direction D, and a facing attitude in which the engaging piece L1 faces the FOUP 4 (the attitude shown in FIG. 8). In the load port 2 according to the present embodiment, the mounting table 23 on which the FOUP 4 is mounted is positioned at a predetermined docking position where the FOUP door 43 approaches the opening 215 by setting the engaging piece L1 in a non-facing position. , and a position spaced apart from the transfer chamber 3 by a predetermined distance from the docking position. In other words, the movement restricting portion L enters the movement permitting state by setting the engaging piece L1 to the non-facing posture.

Such a movement restricting portion L is configured so that after the mounting table 23 in the undocking position is moved to the docking position with the FOUP 4 placed thereon, with the engaging piece L1 in the non-facing position, the non-facing position is set. The engaging piece L1 in the posture is moved in the direction to be drawn toward the transfer chamber 3 to change from the non-face-to-face posture to the face-to-face posture. Then, the engaging piece L1 can be engaged with the flange portion 45 projecting outward from the rear surface 42B of the FOUP body 42. As shown in FIG. Then, by pulling the engaging piece L1 toward the transfer chamber 3 side by the retracting portion L2, the engaging piece L1 moves toward the transfer chamber 3 side (rear) while maintaining the engaged state between the engaging piece L1 and the flange portion 45 of the FOUP 4. drawn into. As a result, the flange portion 45 of the FOUP 4 is sandwiched between the engaging piece L1 and the base 21, thereby restricting the FOUP 4 on the mounting table 23 positioned at the docking position from moving away from the base 21. can be done. That is, the movement restricting portion L changes the engaging piece L1 from the non-facing posture to the facing posture, and draws the engaging piece L1 toward the base 21 by the retracting portion L2, thereby moving the restricting state (the state shown in FIG. 8). )become.

In the load port 2 of the present embodiment, such movement restricting portions L are provided near the upper end and near the lower end on both sides of the substantially rectangular opening 21a of the base 21, as shown in FIGS. They are placed at four locations in total. Specifically, in the window frame portion 216 of the window unit 214 , the movement restricting portions L are arranged at a total of four locations spaced apart in the vertical direction on both sides of the substantially rectangular opening 215 .

In this embodiment, as shown in FIG. 9, the rear surface 42B of the FOUP body 42 of the FOUP 4 mounted on the mounting table 23 positioned at the docking position is separated from the front surface 21A ( The front surface 216</b>A) of the window frame portion 216 is approached, and the first seal portion 5 is configured to be able to seal the gap therebetween. Further, in the load port 2 of the present embodiment, if the load port door 22 is in the closed state after the mounting table 23 is positioned at the predetermined docking position, the FOUP door 43 and the load port door 22 form a gap of a predetermined size. The load port door 22 and the base 21 are configured so that they can be sealed by the second seal portion 6 while they are separated from each other. Therefore, the space where the load port door 22 and the FOUP door 43 face each other across a gap of a predetermined size forms a sealed space DS partitioned by the first seal portion 5 and the second seal portion 6 .

As shown in FIGS. 5 and 9, the load port door 22 according to the present embodiment includes a gas injection portion 71 for injecting gas into the closed space DS and a gas discharge portion 72 for discharging gas from the closed space DS. and The gas injection unit 71 is configured using, for example, a long nozzle, and one end of the nozzle (downstream end in the gas injection direction) reaches the outer surface of the load port door 22, and the other end of the nozzle (gas injection direction) reaches the outer surface of the load port door 22. A gas injection valve 71a is connected in the vicinity of the direction upstream end). Similarly, the gas discharge section 72 is configured using, for example, a nozzle, and one end of the nozzle (upstream end in the gas discharge direction) reaches the outer surface of the load port door 22, and the other end of the nozzle (gas discharge direction upstream end) reaches the outer surface of the load port door 22. A gas discharge valve 72a is connected in the vicinity of the direction downstream end). With such a configuration, an environmental gas (nitrogen gas in this embodiment) is supplied to the closed space DS by the gas injection part 71, and the closed space DS is exhausted by the gas discharge part 72, thereby gas purging the closed space DS. is possible. The "door purge process" in the present invention is the gas purge process of replacing the sealed space DS, which is opposed to the FOUP door 43 and the load port door 22 with a predetermined gap, with gas.

As shown in FIG. 5, the upstream end of the gas injection part 71 in the gas injection direction, the gas injection valve 71a, the downstream end of the gas discharge part 72 in the gas discharge direction, and the gas discharge valve 72a are covered with the cover 28 described above. A predetermined portion of each nozzle constituting the gas injection portion 71 and the gas discharge portion 72 penetrates the load port door 22 in the thickness direction (the front-rear direction D). The portion of the load port door 22 through which the nozzle penetrates is appropriately sealed. In this embodiment, a nozzle that is excellent in flexibility or stretchability (including bellows type) is used. A tube may be substituted for part or all of the nozzle. In FIG. 5, etc., the portions of the gas injection section 71 and the gas discharge section 72 that are exposed to the transfer space 3S are actually located inside a door cover (not shown) that covers the load port door 22 from the transfer chamber 3 side. It is contained.

The load port 2 configured as described above executes a predetermined operation by giving a drive command to each part from the control part 2C. In the EFEM 1 of this embodiment, a plurality (eg, three) of such load ports 2 are arranged side by side on the front wall surface 3A of the transfer chamber 3 .

As shown in FIG. 1, the EFEM 1 is mainly composed of a load port 2 and a transfer chamber 3 which are provided adjacent to each other in a common clean room. The operation of the EFEM 1 is controlled by the controller of the load port 2 (the controller 2C shown in FIG. 2) and the controller of the entire EFEM 1 (the controller 3C shown in FIG. 1).

A processing apparatus M (semiconductor processing apparatus), for example, is provided adjacent to a rear wall surface 3B of the transfer chamber 3 that faces a front wall surface 3A on which the load port 2 is arranged. In the clean room, the internal space MS of the processing equipment M, the internal space 3S of the transfer chamber 3, and the internal space 4S of the FOUP 4 placed on the load port 2 are maintained at a high degree of cleanliness. On the other hand, the space in which the load port 2 is arranged, in other words, the outside of the processing apparatus M and the outside of the EFEM 1 has a relatively low degree of cleanliness. 1 is a side view schematically showing the relative positional relationship between the load port 2 and the transfer chamber 3, and the relative positional relationship between the EFEM 1 having the load port 2 and the transfer chamber 3, and the processing apparatus M. be.

The processing apparatus M includes a load lock chamber located relatively close to the transfer chamber 3 and a processing apparatus main body located relatively far from the transfer chamber 3 . In this embodiment, as shown in FIG. 1, the load port 2, the transfer chamber 3, and the processing apparatus M are closely arranged in this order in the front-rear direction D of the EFEM 1. As shown in FIG. The operation of the processing device M is controlled by the controller of the processing device M (control unit MC shown in FIG. 1). Here, the control unit MC as the controller of the entire processing apparatus M and the control unit 3C as the controller of the entire EFEM 1 are superordinate controllers of the control unit 2C of the load port 2 .

The transfer chamber 3 is provided with a transfer robot 31 capable of transferring a wafer W, which is an object to be transferred, between the FOUP 4 and the processing apparatus M in the internal space 3S. The transfer robot 31 includes, for example, a plurality of link elements that are horizontally rotatably connected to each other, an arm provided with a hand at the distal end, and an arm base that constitutes the proximal end of the arm. and a traveling portion that travels in the width direction of the load port 2 (parallel direction of the load port 2). It is of variable link structure (multi-joint structure). It is also possible to construct an EFEM in which either one or both of the buffer station and the aligner are arranged on the side of the transfer chamber 3 .

By connecting the load port 2 and the processing apparatus M, the transfer chamber 3 is in a state in which the internal space 3S is substantially sealed. The interior of the transfer chamber 3 can be purged with a predetermined gas (inert gas or environmental gas such as nitrogen gas) using a gas supply port and a gas discharge port (not shown) to increase the concentration of the environmental gas. It's becoming A fan filter unit 32 is provided in the upper portion of the wafer transfer chamber 3 to send gas downward and suck the gas through a chemical filter provided in the lower portion. The sucked gas is returned toward the upper fan filter unit 32 via the circulation duct 321 . By doing so, a down flow, which is an air current directed downward from above, is formed in the internal space 3</b>S of the transfer chamber 3 . Therefore, the environmental gas in the transfer chamber 3 can be circulated and maintained in a clean state. In addition, even if particles that contaminate the surface of the wafer W exist in the inner space 3S of the transfer chamber 3, the particles are pushed downward by the downflow, and adhesion of the particles to the surface of the wafer W being transferred is suppressed. It becomes possible to In FIG. 1, the flow of gas through the fan filter unit 32 is schematically shown by arrows.

The load port 2 according to this embodiment executes a predetermined operation by giving a drive command to each part from the control part 2C. In this embodiment, the control unit 2C of the load port 2 is configured to give drive commands to each unit. The control unit 2C is composed of a normal microprocessor or the like having a CPU, memory, and an interface. Programs necessary for processing are stored in advance in the memory, and the CPU sequentially retrieves and executes the necessary programs. It is designed to achieve the desired functions in cooperation with peripheral hardware resources.

Next, the operation flow of the EFEM 1 will be described together with the method of using the EFEM 1 having the load port 2 and its operation.

First, the FOUP 4 is moved to above the load port 2 by a container conveying device such as an OHT which operates on a straight conveying line (flow line) extending along the common front wall surface 3A on which the load port 2 is arranged in the conveying chamber 3. It is transported and mounted on the mounting table 23 . At this time, for example, the positioning projections 231 provided on the mounting table 23 are fitted into the positioning recesses of the FOUP 4 . Further, the control unit 2C locks the lock claw 232 on the mounting table 23 (locking process). Specifically, the locking claw 232 on the mounting table 23 is hooked to a locked portion (not shown) provided on the bottom surface of the FOUP 4 to lock the FOUP 4 . As a result, the FOUP 4 can be mounted and fixed at a predetermined regular position on the mounting table 23 . In the present embodiment, the FOUPs 4 can be placed on each of the three FOUPs 23 of the load port 2 arranged side by side in the width direction of the transfer chamber 3 . A seat sensor (not shown) for detecting whether or not the FOUP 4 is placed on the mounting table 23 at a predetermined position detects that the FOUP 4 is placed on the mounting table 23 at a proper position. It can also be configured.

Next, in the load port 2 of the present embodiment, the controller 2C moves the mounting table 23 from the position shown in FIG. 5 to the docking position shown in FIG. 6 (docking process). 5 is moved toward the base 21, and the rear surface of the FOUP 4 is placed on the front surface 21A of the base 21 closest to the FOUP main body 42 at the periphery of the opening 21a. The rear surface 42B of the FOUP body 42 and the outward surface of the FOUP door 43) are brought close to each other by a predetermined distance. Until this docking process is executed, the movement restricting portion L is maintained in the movement permitting state in which the engaging piece L1 is in the non-facing posture. 5 and the like is the farthest rearmost surface of the base 21 from the FOUP main body 42 at the periphery of the opening 21a (the opening 215 of the window frame 216).

Then, when the mounting table 23 is moved to a predetermined docking position, in the load port 2 of the present embodiment, the control section 2C uses the movement restricting section L to hold and fix at least both sides of the FOUP 4. . Specifically, the engaging piece L1 is pulled toward the base 21 by the retracting portion L2 of the movement restricting portion L. As shown in FIG. Then, the engaging piece L1 switches from the non-facing posture to the facing posture, and engages with the flange portion 45 of the FOUP main body 42 . In this state, the collar portion 45 of the FOUP 4 on the mounting table 23 positioned at the docking position is sandwiched between the engaging piece L1 of the movement restricting portion L and the front surface 21A of the base (the front surface 216A of the window frame portion 216). can be done. That is, the container clamping process can be realized by switching the movement restricting portion L from the movement permitting state to the movement restricting state.

The timing of switching the movement restricting portion L from the movement permitting state to the movement restricting state may be after the mounting table 23 is positioned at the docking position. A configuration may be adopted in which L is switched from the movement-permitting state to the movement-restricting state. Alternatively, the movement restricting portion L may be switched from the movement-permitting state to the movement-restricting state after a predetermined time has passed since the mounting table 23 is positioned at the docking position.

Then, in the load port 2 of the present embodiment, when the container clamping process is completed, the loading table 23 positioned at the docking position is placed in the vicinity of the opening 21a of the base 21 (the opening 215 of the window frame 216). Of the placed FOUP 4, the rear surface 42B of the FOUP main body 42, which is set as the sealing surface, is in elastic contact with the first seal portion 5 of the base 21, and the elastic deformation of the first seal portion 5 causes good separation between the FOUP 4 and the base 21. A tight seal area can be formed. That is, in the load port 2 of this embodiment, by performing the container clamping process, the process (sealing process) for forming a good sealing area between the FOUP 4 and the base 21 can be performed at the same time.

Specifically, the portion with which the first seal portion 5 is elastically contacted is the portion of the rear surface 42B of the FOUP body 42 that circulates in the vicinity of the loading/unloading port 41 of the FOUP 4 . In the load port 2 of the present embodiment, the rear surface 42B of the FOUP body 42 is used as the sealing surface, forming a sealing area that can immediately follow even if the sealing surface fluctuates due to vibration or the like. In the load port 2 of the present embodiment, the FOUP 4 on the mounting table 23 positioned at the docking position can be maintained fixed by the movement restricting portion L by performing the container clamping process. Therefore, it is possible to prevent the FOUP 4 in elastic contact with the first seal portion 5 from moving away from the base 21 or tilting. In particular, in the present embodiment, the movement restricting portions L arranged at a total of four locations near the upper end and near the lower end on both sides of the substantially rectangular opening 215 cause the front end portion of the FOUP main body 42 to move around the upper end on both sides and A total of four points near the lower end can be fixed.

In the load port 2 of the present embodiment, following the container clamping process and the sealing process, the control unit 2C supplies nitrogen gas to the closed space DS and removes the gas (atmosphere) that had remained in the closed space DS until then. A process of discharging by the discharge unit 72 is performed (door purge process). The door purge process is a process of injecting nitrogen gas supplied from an appropriate gas supply source into the closed space DS to replace the inside of the closed space DS with nitrogen gas. Specifically, by opening the door purge gas injection valve 71a, the nitrogen gas is supplied from the gas injection part 71 into the closed space DS, and at the same time, by opening the door purge gas discharge valve 72a, the nitrogen gas remains in the closed space DS until then. This is the process of discharging the gas (atmosphere) from the gas discharge section 72 . Here, the atmosphere includes oxygen, moisture, particles, etc., which may change the properties of the wafer W, such as oxidizing the wafer W. If the inside of the FOUP door 43 is hollow and the internal space of the FOUP door 43 communicates with the closed space DS through a hole (door holding hole or the like) formed in the rear surface of the FOUP door 43, this embodiment can be performed. It is possible to replace the internal space of the FOUP door 43 with nitrogen gas by the door purge process of .

In this embodiment, the closed space DS is set to have a positive pressure by increasing the amount of nitrogen gas supplied during the door purge process than the amount of nitrogen gas discharged. Then, as shown in FIG. 10, at an appropriate timing after the pressure in the sealed space DS becomes positive, the priority opening portion X (in this embodiment, the central portion in the width direction of the upper side portion 5A) of the first seal portion 5 is opened. ) is opened with priority over other portions of the first seal portion 5 and the second seal portion 6, that is, the non-open portion Y. That is, the preferential opening portion X of the first seal portion 5, which is in elastic contact with the sealing surface of the FOUP 4 with the tip portion flipped up, is elastically deformed by being pressed by the nitrogen gas filled in the sealed space DS, and is preferentially opened. By deforming the tip portion of the portion X in a spring-up direction, the elastic contact state of the FOUP 4 with respect to the sealing surface is released. As a result, the load port 2 according to the present embodiment exhausts the nitrogen gas in the closed space DS from the opened (elastic contact state is released) portion of the first seal portion 5, i.e., the priority open portion X. (The exhaust direction is schematically indicated by an arrow in FIG. 10). Even after the nitrogen gas can be discharged from the priority opening portion X of the first seal portion 5, the nitrogen gas is continuously supplied to and discharged from the sealed space DS, and the gas is continuously filled into the sealed space DS. . After a predetermined period of time has elapsed from the start of the door purge process, the door purge gas injection valve 71a and the door purge gas discharge valve 72a are closed, thereby completing the filling of the closed space DS with the gas. The gas injection operation of injecting gas from the gas injection part 71 into the closed space DS and the discharge operation of discharging the gas from the closed space DS by the gas discharge part 72 may be repeated. The load port 2 of this embodiment can maintain the sealed state of the non-open portion Y of the first seal portion 5 and the non-open portion Y of the second seal portion 6 even during the door purge process.

The load port 2 of this embodiment is provided with an exhaust unit 8 in the vicinity of the priority opening portion X of the first seal portion 5 and under atmospheric pressure outside the closed space DS GS (see FIGS. 9 and 9). 10). The exhaust unit 8 includes an exhaust port 81 having an opening dimension capable of covering a portion of the first seal portion 5 that is opened when the sealed space DS is under positive pressure (priority opening portion X), and gas passing through the exhaust port 81. and a suction tank 82 for sucking the The exhaust unit 8 is connected to an exhaust system (not shown) such as an exhaust blower in the factory where the EFEM 1 is installed so as to forcibly suck and exhaust surplus gas. By arranging an appropriate flow control valve or shield valve between the exhaust blower and the exhaust unit 8, the suction force or discharge amount of the exhaust unit 8 can be adjusted.

Therefore, in the load port 2 according to the present embodiment, nitrogen leaking from the inside of the sealed space DS to the outside GS of the sealed space DS through the preferentially opened portion X of the first seal portion 5 (released from the elastic contact state) is prevented. Gas can be guided into the exhaust unit 8 to be exhausted and sucked. During the execution of the door purge process, at an appropriate timing after the positive pressure in the closed space DS, the amount of nitrogen gas supplied to the closed space DS is adjusted as long as the positive pressure in the closed space DS can be maintained. By reducing the pressure (while decompressing the closed space DS from the positive pressure to approach the atmospheric pressure), it is possible to limit the amount of gas used and the time the gas is used, thereby reducing costs. Moreover, by providing an oxygen concentration meter for measuring the oxygen concentration in the exhaust unit 8, the oxygen concentration in the exhaust unit 8 can be grasped. When the detection value of the oxygen concentration meter can be input to the control unit, appropriate control can be performed according to the detection value of the oxygen concentration meter.

In the load port 2 of the present embodiment, following the door purge process, the controller 2C switches the coupling mechanism 221 to the lid coupled state (lid coupling process). By this process, the FOUP door 43 can be connected by the connecting mechanism 221 to the load port door 22, which has been placed on standby at the fully closed position (C) in advance, and can be held facing each other with a predetermined gap therebetween. Also, the FOUP door 43 can be removed from the FOUP main body 42 . In addition, in the load port 2 of the present embodiment, when the FOUP 4 is placed on the mounting table 23 at the normal position, the control unit 2C causes the pressure sensor provided on the mounting table 23, for example, to be pressed by the FOUP 4. Of these, it detects that the bottom portion has been pressed. Triggered by this, the control unit 2C issues a drive command (signal) to move the nozzles 261 provided on the mounting table 23 (all the nozzles 261 including the nozzle functioning as the gas introduction section) above the upper surface of the mounting table 23. give. As a result, these nozzles 261 are connected to the inlet and outlet of the FOUP 4, respectively, to supply nitrogen gas to the internal space 4S of the FOUP 4, to discharge the gas atmosphere in the FOUP 4, and to fill the internal space 4S of the FOUP 4 with nitrogen gas. , the moisture concentration and oxygen concentration in the FOUP 4 are lowered to a predetermined value or less, respectively, to make the surrounding environment of the wafer W in the FOUP 4 a low-humidity environment and a low-oxygen environment (bottom purge process).

In the load port 2 of the present embodiment, following the lid connecting process, the control unit 2C moves the FOUP door 43 together with the load port door 22 to open the opening 21a of the base 21 and the loading/unloading port 41 of the FOUP 4. Then, a process for releasing the sealed state inside the FOUP 4 (container unsealing process) is executed. Specifically, as shown in FIG. 7, the control unit 2C moves the load port door 22 from the fully closed position (C) by the door moving mechanism 27 toward the transfer chamber 3 side in the internal space 5S of the chamber 5 as described above. The load port door 22 is moved along the horizontal path to the above-described open position (O), and the load port door 22 that has reached the above-described open position (O) is lowered by a predetermined distance along the above-described vertical path to the fully open position (not shown). ). At the start of the execution of the container sealing release process, the sealed space DS and the internal space 4S of the FOUP 4 are filled with nitrogen gas by the door purge process and the bottom purge process (container interior purge process), so the load port door 22 is transported. During the process of moving the chamber 3 to the inner space 3S side, it is possible to prevent the particles and the like adhering to the FOUP door 43 before the execution of the door purge process from scattering.

As a result, the internal space 4S of the FOUP body 42 and the internal space 3S of the transfer chamber 3 are brought into communication with each other. The downward current of nitrogen generated in the transfer space 3S is also kept clean. Here, when the container sealing release process is performed, if the volume (capacity) of the sealed space DS increases, the sealed space DS is likely to have a negative pressure, and there is a possibility that the atmosphere may enter the sealed space DS from the external space GS. Therefore, in the present embodiment, the container sealing release process is performed while the sealed space DS is in a positive pressure state with respect to the external space GS. Specifically, the nitrogen gas continues to be supplied from the gas injection unit 71 even when the container sealing release process is executed. In this way, in the present embodiment, the container sealing release process is performed in a state where the sealed space DS is at least not under a negative pressure. Further, in the container sealing release process, it is preferable that the sealed space DS is opened with a pressure similar to that of the transfer space 3S. The differential pressure between the outer space GS and the transfer space 3S is 3 to 500 Pa (G), preferably 5 to 100 Pa (G). With the inner space 4S of the FOUP main body 42 and the inner space 3S of the transfer chamber 3 communicated by the container sealing release process, the transfer robot 31 provided in the inner space 3S of the transfer chamber 3 accesses the inside of the FOUP 4 to transfer the wafer. A transport process is performed for W (transport process). Contents of the transfer process that can be carried out in the transfer process include a process in which the transfer robot 31 takes out the wafer W from the FOUP 4 by hand, and a process by which the processed wafer W that has undergone appropriate processing by the processing apparatus M is put into the FOUP 4 by hand. is. For example, when the wafer W in the FOUP 4 is transferred into the transfer chamber 3 by the transfer process, the wafer W transferred into the transfer chamber 3 is transferred to the processing apparatus M (specifically, the load lock chamber) by the transfer robot 31. or transported to a buffer station or aligner. Further, the processed wafer W, which has been appropriately processed by the processing equipment M, is directly stored in the internal space 4S of the FOUP 4 from the internal space MS of the processing equipment M by the transfer robot 31, or is transferred to the FOUP 4 after passing through the buffer station. are sequentially accommodated in the internal space 4S of the .

Then, in the load port 2 according to the present embodiment, when executing the next access of the transport robot 31 to the FOUP 4, the transport process is repeated. In the load port 2 according to the present embodiment, when all the wafers W in the FOUP 4 have finished the processing process by the processing apparatus M, the control unit 2C causes the door moving mechanism 27 to move the load port door 22 to the fully closed position (C ) to close the opening 21a of the base 21 and the loading/unloading port 41 of the FOUP 4 to seal the internal space 4S of the FOUP 4 (container sealing process).

Subsequently, the control unit 2C executes a process of switching the connection mechanism 221 from the lid-connected state to the lid-disconnected state (lid-disconnection process). By this process, the connection state (lid connection state) between the load port door 22 and the FOUP door 43 by the connection mechanism 221 is released, and the FOUP door 43 can be attached to the FOUP main body 42 . As a result, the opening 21a of the base 21 and the loading/unloading port 41 of the FOUP 4 are closed by the load port door 22 and the FOUP door 43, respectively, and the internal space 4S of the FOUP 4 is sealed.

In the load port 2 according to the present embodiment, when the door purge process is stopped, the sealed space DS is no longer in a positive pressure state, and the portion of the first seal portion 5 that was opened during the door purge process (priority open portion X) is elastically restored. and make elastic contact with the sealing surface of the FOUP 4 . However, it is essential to maintain the positive pressure state of the sealed space DS in order to avoid the above-described problems caused by the non-positive pressure state of the sealed space DS.

Subsequently, in the load port 2 according to the present embodiment, the control section 2C performs container clamp release processing for releasing the fixed state (clamped state) of the FOUP 4 by the movement restricting section L. FIG. Specifically, the engaging piece L1 at a position pulled toward the base 21 by the retracting portion L2 of the movement restricting portion L is moved away from the base 21 . Then, the engaging piece L1 is automatically switched from the facing posture to the non-facing posture, the engaging state of the engaging piece L1 with respect to the flange portion 45 of the FOUP body 42 is released, and the fixed state of the FOUP 4 by the movement restricting portion L is released. can do. That is, the container clamp releasing process can be realized by the process of switching the movement restricting portion L from the movement restricting state to the movement permitting state.

Next, in the load port 2 of the present embodiment, the controller 2C executes processing (docking release processing) for moving the mounting table 23 away from the base 21 . Further, the control unit 2C releases the locked state of the FOUP 4 with the lock claws 232 on the mounting table 23 (unlock processing). Specifically, the locked state of the lock claw 232 with respect to the locked portion provided on the bottom surface of the FOUP 4 is released. As a result, the FOUP 4 storing the wafers W that have undergone the predetermined processing is handed over from the mounting table 23 of each load port 2 to the container transfer device and carried out to the next process.

As described above, in the load port 2 according to the present embodiment, when the load port door 22 is in the closed state and the container 4 is in contact with the base 21 via the first seal portion 5, the load port door 2 is closed. 22 and the FOUP door 43 face each other across a gap of a predetermined size to form a closed space DS partitioned by a first seal portion 5 and a second seal portion 6, and gas is supplied to this closed space DS. and is capable of executing a door purge process for replacing the closed space DS with gas. When the load port door 22 is opened, the atmosphere containing oxygen, moisture, particles, etc., which may change the properties of the wafer W such as oxidizing the wafer W by existing between the transfer space 3S and the inside of the FOUP 4 It is possible to prevent and control the situation that flows into That is, before the FOUP door 43 is opened to open the closed space DS, oxygen, moisture, and particles in the closed space DS can be removed.

In addition, in the load port 2 according to the present embodiment, part or all of the first seal portion 5, which is the seal portion on the FOUP 4 side, of the first seal portion 5 and the second seal portion 6 is closed during the door purge process. By setting DS to a positive pressure, it is set as a priority opening portion X that is opened with priority over the second seal portion 6, and at least the gas in the closed space DS (before the execution of the door purge process) in the closed space DS is passed through this opened portion. air, particles, etc. existing in the closed space DS) can be exhausted to the outside GS. At the time before the door purge process is executed, the atmosphere containing particles adhering to the FOUP door 43 and oxygen, moisture, particles, etc. existing between the FOUP door 43 and the load port door 22 is removed from the sealed space DS to the transfer space 3S. It is possible to prevent the situation from flowing into As a result, a high degree of cleanliness can be maintained in the FOUP 4, the closed space DS, and the transfer space 3S, and a large amount of gas can be supplied to the closed space DS in a short period of time to bring the closed space DS into a positive pressure state. , the tact time can be shortened compared to the mode in which the gas is gradually supplied to the closed space DS to adjust the pressure while removing dust and the like in the closed space DS.

Furthermore, according to the load port 2 according to the present embodiment, there is no need for special control such as making the pressure in the sealed space DS equal to the pressure in other spaces (the internal space 4S of the FOUP 4, the transfer space 3S, etc.). Cost reduction and takt time can be shortened by eliminating control equipment (valves and piping) for control.

In particular, since the load port 2 according to the present embodiment has a configuration in which the exhaust unit 8 is provided near the preferential opening portion X and under atmospheric pressure, which is the outside GS of the closed space DS, the pressure in the closed space DS The exhaust unit 8 efficiently exhausts at least gas such as the door purge gas that leaks out of the closed space DS from the priority opening portion X set in the first seal portion 5, which is the seal portion on the FOUP 4 side, to the outside GS of the closed space DS. can do. In particular, in this embodiment, a gas discharge portion 72 for discharging the gas in the closed space DS is provided together with the gas injection portion 71 in order to form a gas flow in the closed space DS. Here, if a configuration is adopted in which the gas exhaust part 72 for exhausting the gas in the closed space DS is not provided, the inside of the closed space DS is released only from the portion of the closed space DS where the sealed state is opened (prioritized open portion X). As the gas escapes, there is a possibility that there will be a place in the closed space DS where it is difficult for the gas to be replaced. On the other hand, in the present embodiment, since the configuration including the gas exhaust portion 72 for actively exhausting the gas in the closed space DS is adopted, compared to the configuration without the gas exhaust portion 72, the closed space DS It is possible to prevent/suppress the occurrence of a place where it is difficult for gas to be replaced. It should be noted that it is not an essential requirement that the gas discharge part 72 be one that sucks, but it may be one that is open to the atmosphere. In the case of opening to the atmosphere, it is preferable to increase the diameter of the pipe (exhaust pipe) forming the gas discharge portion 72. More specifically, the pipe (supply pipe) forming the gas injection portion 71 has a larger diameter. Larger is desirable. In addition, by adopting a mode in which a plurality of gas injection parts 71 and gas discharge parts 72 are provided, it is possible to prevent or suppress the occurrence of places where it is difficult for gas to be replaced in the closed space DS with a higher probability. Note that the present invention also includes a configuration in which the gas discharge section 72 is intentionally omitted as an example of the EFEM according to the present embodiment.

Assuming that the embodiment described above is the first embodiment, the load port 2 according to the second embodiment of the present invention will be described below.

The load port 2 according to the second embodiment has substantially the same configuration as the load port 2 according to the first embodiment. The difference is that the closed space DS is set to a priority open portion X that is opened with priority over the second seal portion 6 by setting the sealed space DS to a negative pressure. In the following description and FIGS. 11 and 12, the same reference numerals are given to the parts of the load port 2 according to the first embodiment and the parts corresponding to the parts.

The first seal portion 5 provided in the load port 2 according to the second embodiment is provided so as to surround the opening 21a in the region near the opening edge of the opening 21a on the front surface 21A of the base 21, and the FOUP 4 is attached to the base 2. It seals between the periphery of the opening 21a of the base 21 and the FOUP 4 when positioned at a predetermined front position (see FIG. 11). In this embodiment, which employs a configuration in which the window unit 214 is attached to the base 21, the first seal portion is positioned around the opening 215 in the region near the opening edge of the opening 215 on the front surface 216A of the window frame portion 216. 5 is provided. Specifically, in the front surface 216A of the window frame portion 216, the first seal surface (the surface of the FOUP body 42 set around the FOUP door 43), which is the rear surface 42B of the FOUP body 42, is opposed to the first sealing surface. The seal part 5 is made to go around and attached. The first seal portion 5 arranged so as to surround the rectangular opening 215 near the edge of the opening 215 has a substantially rectangular shape when viewed from the FOUP 4 side. Therefore, the first seal portion 5 includes an upper side portion 5A arranged near the upper edge of the opening 215, a lower side portion 5B arranged near the lower edge of the opening 215, and both side edges of the opening 215. It can be roughly divided into the side portions 5C that are arranged in the vicinity of each other. The first seal portion 5 of this embodiment, which has a basic shape of a rectangle having these four sides, has a shape in which the four corners are smoothly connected by circular arcs.

In this embodiment, an O-ring having a substantially circular cross-sectional shape is applied as the first seal portion 5, and the common O-rings are the upper side portion 5A, the lower side portion 5B, and the left and right side portions of the first seal portion 5. It is arranged over 5C. As described above, in the present embodiment, the entire first seal portion 5 is formed of an elastic body (circular elastic body D1) having a substantially circular cross-sectional shape, and the entire first seal portion 5 serves as the "unopened portion Y". have set.

Such a first seal portion 5 is interposed between the FOUP 4 mounted on the mounting table 23 positioned at the docking position and the peripheral edge of the opening 21a of the base 21 to exhibit a sealing function.

FIG. 11 shows a state in which the first seal portion 5 is in elastic contact with the FOUP 4 mounted on the mounting table 23 positioned at the predetermined docking position. In the load port 2 of the present embodiment, the first seal portion 5 is arranged in a form in which the first seal portion 5 protrudes from the end surface of the load port door 22 closest to the FOUP 4 toward the FOUP 4 by a predetermined dimension L2 (for example, 0.1 mm or more and 3 mm or less). is doing. Therefore, the FOUP door 43 and the load port door 22 do not come into contact with each other, and the high sealing performance of the sealed space DS formed between the base 21 and the load port door 22 can be maintained by the first seal portion 5 . .

That is, as shown in FIG. 11, the first seal portion 5 is in elastic contact with the rear surface 42B of the FOUP main body 42 mounted on the mounting table 23 positioned at the predetermined docking position. Specifically, the entire first seal portion 5 is brought into elastic contact with the rear surface 42B of the FOUP main body 42 mounted on the mounting table 23 positioned at the predetermined docking position. It elastically deforms into a shape crushed in the front-rear direction D from the time of . By maintaining such an elastic contact state between the first seal portion 5 and the FOUP 4, a good seal area can be formed.

The second seal portion 6 is provided on the rear surface 21B of the base 21 so as to surround the opening 21a in a region near the edge of the opening 21a. In this embodiment, which employs a configuration in which the window unit 214 is attached to the base 21, the second seal portion is provided at a position surrounding the opening portion 215 in the region near the opening edge of the opening portion 215 on the rear surface 216B of the window frame portion 216. 6 is provided. Specifically, of the rear surface 216B of the window frame portion 216, it faces the front surface of the load port door 22, that is, the seal surface set in a predetermined portion of the entire surface 21A of the base (the surface set in the outer edge portion of the load port door 22). The second seal portion 6 is mounted around the position where it is located. In the present embodiment, a brim-shaped thin-walled portion formed on the outer peripheral edge of the load port door 22 is set as the sealing surface of the load port door 22 . The second seal portion 6 arranged so as to surround the opening 215 in the vicinity of the opening edge of the rectangular opening 215 has a substantially rectangular shape when viewed from the transfer chamber 3 side.

In this embodiment, most of the second seal portion 6 is formed of an elastic body (circular elastic body D1) having a substantially circular cross-sectional shape, and a part of the second seal portion 6 is formed of an elastic body having a substantially circular cross-sectional shape that is more likely to be elastically deformed than the elastic body having a substantially circular cross-sectional shape. It is formed by a body (non-circular elastic body D2). Specifically, predetermined portions of the second seal portion 6 including the entire lower side portion 6B, the entire left and right side portions 6C, and both width direction end portions of the upper side portion 6A are formed of the circular elastic body D1, and the second seal portion 6, the central portion in the width direction of the upper side portion 6A is formed of a non-circular elastic body D2. The non-circular elastic body D2 of the present embodiment has a rod-shaped cross section (a rod shape whose longitudinal dimension in the cross-sectional view is larger than the diameter of the substantially circular elastic body) and has a rounded tip portion at the rear ( side of the transfer chamber 3) (a hanging posture, a posture in which the tip portion deforms toward the inside of the closed space DS).

Then, when the load port door 22 is positioned at the closed position, the load port door 22 (more specifically, the thin portion) contacts the rear surface 216B of the window frame portion 216 via the second seal portion 6. As a result, the second seal portion 6 seals between the peripheral edge of the opening 21a of the base 21 and the load port door 22 (see FIG. 11). In particular, the preferential opening portion X of the second seal portion 6 is brought into elastic contact with the load port door 22, so that the tip portion is positioned downward (in the direction toward the sealed space DS) from before the elastic contact with the load port door 22. It elastically deforms into a depressed form. As a result, when the load port door 22 is positioned at the closed position, gas flows out from the internal space 3S of the transfer chamber 3 to the outside of the transfer chamber 3, or from the outside of the transfer chamber 3 to the internal space 3S of the transfer chamber 3. of gas can be suppressed. In a state in which the second seal portion 6 exerts the sealing function, the second seal portion 6 receives a predetermined pressure between the sealed space DS including the sealed area by the second seal portion 6 and the internal space 3S of the transfer chamber 3. As a result, the preferential opening portion X of the second seal portion 6 is unsealed and opened with priority over the non-opening portion Y, as shown in FIG.

In the load port 2 of the present embodiment, the front surface 216A and the rear surface 216B of the window frame portion 216 are provided with mounting grooves each having a concave shape in cross section so as to go around the vicinity of the opening edge of the opening 215 (the second groove in FIGS. 11 and 12). A concave portion in which the first seal portion 5 and the second seal portion 6 are fitted is formed. The first seal portion 5 and the second seal portion 6 are inserted into the respective seal mounting grooves and tightly mounted. In particular, the seal mounting groove in which the preferential opening portion X of the second seal portion 6 is attached is set to have a trapezoidal cross section that gradually widens toward the depth of the groove, and the base of the preferential opening portion X is set in this trapezoidal seal mounting groove. It is fixed by an appropriate means such as an adhesive agent in a state where the insertion portion provided at the end is fitted. This prevents the priority opening portion X of the second seal portion 6 from slipping out of the seal mounting groove. In this attached state, portions of the first seal portion 5 and the second seal portion 6 that are not accommodated in the attachment groove are exposed outside the attachment groove.

In this embodiment, when the mounting table 23 is positioned at the predetermined docking position, the rear surface 42B of the FOUP body 42 approaches the front surface 21A of the base 21 (the front surface 216A of the window frame portion 216) with a gap of a predetermined size. , the gap can be sealed by the first seal portion 5 . Further, in the load port 2 of the present embodiment, if the load port door 22 is in the closed state after the mounting table 23 is positioned at the predetermined docking position, the FOUP door 43 and the load port door 22 form a gap of a predetermined size. The load port door 22 and the base 21 are configured so that they can be sealed by the second seal portion 6 while they are separated from each other. Therefore, the space where the load port door 22 and the FOUP door 43 face each other across a gap of a predetermined size forms a sealed space DS partitioned by the first seal portion 5 and the second seal portion 6 .

The load port door 22 according to the second embodiment includes a gas injection section 71 for injecting gas into the sealed space DS, and a gas discharge section 72 for discharging the gas from the sealed space DS (corresponding to the "exhaust section" of the present invention). ), a gas such as dry nitrogen gas is supplied to the closed space DS by the gas injection part 71, and the gas (including gas) in the closed space DS is discharged by the gas discharge part 72, thereby gas purging the closed space DS. It is possible to

Then, in the load port 2 of the present embodiment, when the container clamping process is completed, the loading table 23 positioned at the docking position is placed in the vicinity of the opening 21a of the base 21 (the opening 215 of the window frame 216). Of the placed FOUP 4, the rear surface 42B of the FOUP main body 42, which is set as the sealing surface, is in elastic contact with the first seal portion 5 of the base 21, and the elastic deformation of the first seal portion 5 causes good separation between the FOUP 4 and the base 21. A tight seal area can be formed. That is, in the load port 2 of this embodiment, by performing the container clamping process, the process (sealing process) for forming a good sealing area between the FOUP 4 and the base 21 can be performed at the same time.

In the load port 2 of the present embodiment, following the container clamping process and the sealing process, the control unit 2C supplies nitrogen gas to the closed space DS and removes the gas (atmosphere) that had remained in the closed space DS until then. A process of discharging by the discharge unit 72 is performed (door purge process). In this embodiment, the closed space DS is set to have a negative pressure by making the amount of nitrogen gas discharged larger than the amount of nitrogen gas supplied during the door purge process.

Then, as shown in FIG. 12, at an appropriate timing after the sealed space DS becomes negative pressure, the priority opening portion X (in this embodiment, the central portion in the width direction of the upper side portion 6A) of the second seal portion 6 ) is opened with priority over other portions of the second seal portion 6 and the first seal portion 5, that is, the non-open portion Y. That is, the preferential opening portion X of the second seal portion 6, which is in elastic contact with the seal surface of the load port door 22 in a hanging form, is elastically deformed by being pressed by the nitrogen gas filled in the sealed space DS. By deforming the front end of the priority opening portion X in the direction of being pushed down (the direction toward the inside of the closed space DS), the load port door 22 is released from elastic contact with the sealing surface. As a result, the load port 2 according to the present embodiment can move from the internal space 3S of the transfer chamber 3 to the sealed space through the opened portion (the elastic contact state is released) of the second seal portion 6, that is, the preferential open portion X. An airflow directed toward DS is formed (in FIG. 12, an arrow schematically shows the airflow directed from the internal space 3S of the transfer chamber 3 to the closed space DS). Nitrogen gas is continuously supplied to and discharged from the closed space DS even after the airflow passing through the preferential open portion X of the second seal portion 6 is formed, and the closed space DS continues to be filled with gas. After a predetermined period of time has elapsed since the start of the door purge process, the gas filling valve for door purge and the gas discharge valve for door purge are closed, thereby completing the filling of the closed space DS with the gas. The gas injection operation of injecting gas from the gas injection part 71 into the closed space DS and the discharge operation of discharging the gas from the closed space DS by the gas discharge part 72 may be repeated.

In the load port 2 of the present embodiment, the gas discharge portion 72 constitutes a suction path for sucking the inside of the closed space DS, and the discharge portion 72 functions as an exhaust unit. The exhaust unit is connected to an exhaust system (not shown) such as an exhaust blower in the factory where the EFEM 1 is installed so as to forcibly suck and exhaust surplus gas. By arranging an appropriate flow control valve or shield valve between the exhaust blower and the exhaust unit, the suction force or discharge amount of the exhaust unit can be adjusted.

During execution of the door purge process, the load port 2 according to the present embodiment is closed as long as the negative pressure state in the closed space DS can be maintained at an appropriate timing after the inside of the closed space DS becomes negative pressure. By reducing the amount of nitrogen gas supplied to the space DS, it is possible to limit the gas usage amount and the gas usage time, thereby reducing costs. In addition, by providing an oxygen concentration meter for measuring the oxygen concentration in the exhaust unit, the oxygen concentration in the exhaust unit can be grasped, and the detection value of the oxygen concentration meter can be input to the control unit. , it is possible to perform appropriate control according to the detected value of the oximeter. It should be noted that, when the container sealing release process is performed, there is a possibility that air will enter the sealed space DS from the external space GS due to the fact that the sealed space DS is in a negative pressure state. Therefore, also in the present embodiment, it is preferable to perform the container sealing release process in a state where the sealed space DS has a positive pressure with respect to the external space GS. Specifically, by continuing to supply nitrogen gas from the gas injection part 71 even when executing the container unsealing process, the container unsealing process can be performed while the sealed space DS is at least not under a negative pressure.

The load port 2 according to the second embodiment performs a door purge function to remove particles adhering to the FOUP door 43 and wafers W that exist between the FOUP door 43 and the load port door 22. Prevents and suppresses the situation in which the atmosphere containing oxygen, moisture, particles, etc., which may change the properties of the wafer W such as oxidizing the wafer W, flows into the transfer space 3S and the FOUP 4 when the load port door 22 is opened. can. That is, before the FOUP door 43 is opened to open the closed space DS, oxygen, moisture, and particles in the closed space DS can be removed.

Furthermore, in the load port 2 according to the second embodiment, part or all of the second seal portion 6, which is the seal portion on the side of the transfer chamber 3, of the first seal portion 5 and the second seal portion 6 is removed during the door purge process. By setting the closed space DS to a negative pressure, the closed space DS is set as a priority opening portion X which is opened with priority over the first seal portion 5, and an air flow directed from the transfer space 3S to the closed space DS is formed through this opened portion. As a result, the closing force of the FOUP door 43 is weakened due to the negative pressure in the sealed space DS. The closing force of the FOUP door 43 due to the fact that the air containing oxygen, moisture, particles, etc. existing between the port door 22 flows into the FOUP 4 from the sealed space DS or the sealed space DS becomes negative pressure weakens, an air current is formed from the inside of the FOUP 4 toward the closed space DS through the gap between the FOUP door 43 and the FOUP body 42, and the gas (atmosphere) flows back into the FOUP 4 or the closed space DS from the exhaust port at the bottom of the FOUP. Any situation can be prevented. As a result, a high degree of cleanliness can be maintained in the FOUP 4, the closed space DS, and the transfer space 3S, and a large amount of gas can be exhausted from the closed space DS in a short period of time to bring the closed space DS into a negative pressure state. , the tact time can be shortened compared to the mode in which the gas is gradually supplied to the closed space DS to adjust the pressure while removing dust and the like in the closed space DS.

In addition, according to the load port 2 according to the second embodiment, there is no need for special control such as equalizing the pressure in the sealed space DS with the pressure in the other spaces (the internal space 4S of the FOUP 4 and the transfer space 3S). , It is possible to reduce costs and shorten tact time by eliminating the need for control equipment (valves and piping) for control.

In particular, since the load port 2 according to the second embodiment employs a configuration in which an exhaust unit is provided at a predetermined position of the suction path for sucking the inside of the sealed space DS, when the sealed space DS becomes a negative pressure state, In addition, the gas in the closed space DS (door purge gas) can be efficiently exhausted to the outside of the closed space DS GS by the exhaust unit. It is also possible to solve the situation in which the degree of airtightness inside the FOUP 4 is lowered and the air flows back into the FOUP 4 from the exhaust port provided in the FOUP 4 .

Further, since the EFEM 1 according to the first embodiment and the second embodiment includes the load port 2 having the above configuration and the transfer chamber 3 in which the transfer robot is arranged in the transfer space 3S, the load port 2 Objects to be transferred such as wafers W can be transferred between the set FOUP 4 and the transfer chamber 3 by the transfer robot. In addition, it is possible to carry out loading and unloading while maintaining high cleanliness in the transport space 3S. In addition, by obtaining the above-described effects of the load port 2, problems caused by the sealed space DS being in a positive pressure state or a negative pressure state (decreased closing force of the load port door 22, closing force of the FOUP door 43, etc.) contamination of the transfer chamber 3 and the FOUP 4) can be eliminated, and the door purge processing time and the takt time can be shortened.

In addition, the present invention is not limited to each embodiment described above.

The portion that is preferentially opened over the second seal portion (priority opening portion) when the sealed space is in the positive pressure state may be a part of the first seal portion or the entire first seal portion. may be That is, when the sealed space is in a positive pressure state, at least one portion of the first seal portion is set to release the sealed state (a portion where the seal is easily broken) by receiving pressure from the inside of the sealed space to the outside of the sealed space. By doing so, substantially the same effects as those of the load port according to the first embodiment can be obtained. Therefore, it is possible to employ a configuration in which priority opening portions are set at a plurality of locations of the first seal portion.

Further, the present invention provides a configuration in which the priority opening portion of the first seal portion is opened with priority over the second seal portion at the time when the sealed space becomes positive pressure, and the sealed space becomes positive pressure. A configuration in which the preferentially opened portion of the first seal portion is preferentially opened over the second seal portion at an appropriate time point (for example, when the pressure in the sealed space reaches a predetermined value or more) after the time point , any of these configurations may be used.

Similarly, when the sealed space is in a negative pressure state, the portion that is opened with priority over the first seal portion may be a part of the second seal portion or the entire second seal portion. may That is, when the sealed space is in a negative pressure state, a portion (a portion where the seal is likely to be broken) is set at least at the second seal portion where the sealed state is released due to the force of being sucked into the sealed space. Accordingly, substantially the same effects as those of the load port according to the above-described second embodiment can be obtained. Therefore, it is possible to employ a configuration in which priority opening portions are set at a plurality of locations of the second seal portion.

Further, the present invention provides a configuration in which the priority opening portion of the second seal portion is opened with priority over the first seal portion at the time when the sealed space becomes negative pressure, and the sealed space becomes negative pressure. At an appropriate time (for example, when the pressure in the closed space becomes equal to or less than a predetermined value) after that time, the preferentially opened portion of the second seal portion is opened with priority over the first seal portion. Any of these configurations may be used.

The cross-sectional shape and material of the preferential opening portion and the non-opening portion of the first seal portion and the second seal portion are not limited to those of the above-described embodiment, and may be changed as appropriate as long as it is a member that ensures sealing performance (hermeticity).・It is possible to choose. As an example, there is a mode in which both or one of the preferential opening portion and the non-opening portion is configured using a hollow seal portion that expands or contracts due to the introduction or discharge of fluid.

The shape of the seal mounting groove in which the first seal portion and the second seal are mounted can also be changed as appropriate according to the shape of the base end portion (mounting end portion) of the seal portion.

Either a natural exhaust type or a suction exhaust (negative pressure exhaust) type can be selected as appropriate for the exhaust unit. Depending on the position, size, number, etc. of the portion of the first seal portion that is opened with priority over the second seal portion when the sealed space is in a positive pressure state (prioritized opening portion), the number of exhaust ports of the exhaust unit Position, size, number, etc. may be set.

In the above-described embodiment, a FOUP used for wafer transfer is used as a container. However, the container in the present invention is not limited to this, and MAC (Multi Application Carrier), H-MAC (Horizontal-MAC), FOSB (Front Open Shipping Box), etc. can be adopted. Further, the container is not limited to a wafer container, and may be a sealed container that accommodates a contained object (conveyance object) such as an electronic component that is conveyed in a state of being filled with an inert gas.

In the above-described embodiment, the load port is attached to the EFEM. It can also be applied to a sorter equipped with a transfer chamber for exchanging , or an apparatus in which a process device itself is used as a transfer chamber and a load port is attached to the process device itself.

In the embodiment, nitrogen gas is used as an example of the environmental gas used for the door purge process or the like, but it is not limited to this, and a desired gas (inert gas) such as dry gas or argon gas can be used.

In the embodiment, a mode in which the first seal portion and the second seal portion are separately provided was exemplified, but the first seal portion arranged on the front surface of the base, the second seal portion arranged on the rear surface of the base, The load port may be provided with a common seal portion that is integrally provided with a connection portion that connects the first seal portion and the second seal portion and is disposed in a posture that penetrates the base in the thickness direction.

It is also possible to provide a guide that directs the gas from the point where the seal is broken (preferred open portion) to the exhaust unit. Also, if the amount of gas that leaks out of the closed space from the closed space under positive pressure during the door purge process through the priority opening portion is very small (the amount that does not pose a danger to the operator), the exhaust unit can be omitted. can.

In the above-described embodiment, the second sealing portion is provided on the rear surface of the base. A second sealing portion may be used to seal between the load port door and the base in a closed state in which the portion is closed.

The gap dimension that can be sealed by the first seal portion along the thickness direction of the base (the front-rear direction in which the container, the base, and the transfer chamber are arranged), that is, the gap between the base and the container arranged at a predetermined position in front of the base, and the base The dimension of the gap that can be sealed by the second seal portion along the thickness direction of , that is, the gap between the load port door and the base in the closed state with the opening closed may be the same, or may be significantly different. good. This can be dealt with by appropriately changing the shape, material, etc. of the seal portion according to the size of the sealable gap.

The load port door may temporarily assume an inclined posture (accompanied by an operation that draws a partial arc-shaped trajectory) in the process of moving from the closed position to the fully open position.

Further, in the above-described first embodiment, the configuration including the gas supply section and the gas discharge section was exemplified as the load port. can be mentioned. Even with the load port having such a configuration, it is possible to perform the door purge process by the gas supply unit or the closed space cleaning process based on the door purge process, and achieve the same effects as the load port according to the first embodiment. .

In addition, in the above-described second embodiment, the configuration including the gas supply section and the gas discharge section was exemplified as the load port. can be mentioned. Even with the load port having such a configuration, it is possible to perform a process of cleaning the closed space (closed space cleaning process) by discharging the gas in the closed space with the exhaust part (gas outlet part). There exists the effect according to the load port which concerns on 2nd Embodiment.

In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications are possible without departing from the scope of the present invention.

1 EFEM
Reference Signs List 2 Load port 21 Base 21a Opening 22 Load port door 3 Transfer chamber 31 Transfer robot 3S Transfer space 4 Container (FOUP)
43 ... container door (FOUP door)
5 First seal portion 6 Second seal portion 71 Gas injection portion 72 Gas discharge portion (discharge portion)
8 Exhaust unit DS Closed space W Object to be transferred (wafer)
X...Priority opening part

Claims (8)

a base forming part of a wall separating the transfer space from the external space and having an opening through which an object to be transferred can pass;
a load port door that can be engaged with a container door of the container containing the object to be transported and that can open and close the opening of the base;
a first seal portion that seals between a container arranged at a predetermined position in front of the base and the base;
a second sealing portion that seals between the load port door in a closed state with the opening closed and the base;
When the load port door is in the closed state and the container is brought into contact with the base via the first seal portion, the load port door and the container door face each other with a gap of a predetermined size. configuring the space to be a sealed space partitioned by the first seal portion and the second seal portion;
moreover,
a gas injection unit for injecting gas into the closed space;
A priority opening portion in which part or all of the first seal portion is opened with priority over the second seal portion by setting the sealed space to a positive pressure during a door purge process for replacing the sealed space with the gas. , and configured so that at least the gas in the closed space can be exhausted through the opened portion. 2. The load port according to claim 1, further comprising a gas exhaust part for exhausting gas in said closed space. a base forming part of a wall separating the transfer space from the external space and having an opening through which an object to be transferred can pass;
a load port door that can be engaged with a container door of the container containing the object to be transported and that can open and close the opening of the base;
a first seal portion that seals between a container arranged at a predetermined position in front of the base and the base;
a second sealing portion that seals between the load port door in a closed state with the opening closed and the base;
When the load port door is in the closed state and the container is brought into contact with the base via the first seal portion, the load port door and the container door face each other with a gap of a predetermined size. configuring the space to be a sealed space partitioned by the first seal portion and the second seal portion;
moreover,
a gas injection unit for injecting gas into the closed space;
A priority opening portion in which part or all of the first seal portion is opened with priority over the second seal portion by setting the sealed space to a positive pressure during a door purge process for replacing the sealed space with the gas. and configured to be able to exhaust at least the gas in the sealed space through the opened portion,
A load port, wherein an exhaust unit is provided under atmospheric pressure in the vicinity of the preferential opening portion and outside the sealed space. a base forming part of a wall separating the transfer space from the external space and having an opening through which an object to be transferred can pass;
a load port door that can be engaged with a container door of the container containing the object to be transported and that can open and close the opening of the base;
a first seal portion that seals between a container arranged at a predetermined position in front of the base and the base;
a second sealing portion that seals between the load port door in a closed state with the opening closed and the base;
When the load port door is in the closed state and the container is brought into contact with the base via the first seal portion, the load port door and the container door face each other with a gap of a predetermined size. configuring the space to be a sealed space partitioned by the first seal portion and the second seal portion;
moreover,
A discharge unit for discharging the gas in the closed space,
Part or all of the second seal portion is opened preferentially over the first seal portion by setting the sealed space to a negative pressure during the sealed space cleaning process for evacuating the sealed space. A load port characterized by being set to 5. The load port according to claim 4, further comprising a gas injection part for injecting gas into said sealed space. 6. The load port according to claim 4, wherein an exhaust unit is provided at a predetermined position of the suction path for sucking the inside of the closed space. a load port according to any one of claims 1 to 6;
An EFEM comprising a transfer chamber in which a transfer robot is arranged in a transfer space. The transfer chamber is provided with a circulation duct for circulating gas in the transfer space,
8. The EFEM of claim 7, wherein the transfer space has a differential pressure of 3 to 500 Pa (G) with respect to an external space outside the transfer space.

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