Load port and method for driving load port

Abstract

This provides a load port that enhances the airtightness within the EFEM, reduces the amount of gas supplied to the EFEM, and improves wafer quality. [Solution] This device is provided adjacent to the wafer transport chamber and is used for loading and unloading wafers between the wafer transport chamber and the FOUP. It comprises a panel that forms part of the wall surface of the wafer transport chamber and has an opening formed to open the wafer transport chamber, a door for opening and closing the opening, a mounting platform on which the FOUP is placed with a lid that allows the internal space to be opened and closed facing the door and which can move back and forth toward the panel, and an O-ring provided along the periphery of the opening.

Description

Technical Field

[0001] The present invention relates to a load port capable of reducing the amount of gas used even when the wafer transfer chamber has a special gas atmosphere, and an EFEM equipped with the same.

Background Art

[0002] Conventionally, semiconductors have been manufactured by subjecting wafers to various processing steps. In recent years, the high integration of elements and the miniaturization of circuits have been further advanced, 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. Further, in order to prevent the surface properties of the wafer from changing, such as oxidation of the wafer surface, the atmosphere around the wafer is made into a nitrogen atmosphere, which is an inert gas, or a vacuum state. In order to appropriately maintain such an atmosphere around the wafer, the wafer is stored and managed inside a sealed storage pod called a FOUP (Front-Opening Unified Pod), which is filled with nitrogen. Further, in order to transfer the wafer between the processing apparatus that processes the wafer and the FOUP, an EFEM (Equipment Front End Module) as disclosed in Patent Document 1 below is used. The EFEM constitutes a wafer transfer chamber that is substantially closed inside the housing, and includes a load port that functions as an interface portion with the FOUP on one of the opposing wall surfaces, and a load lock chamber that is part of the processing apparatus is connected to the other. A wafer transfer device for transferring the wafer is provided in the wafer transfer chamber, and the wafer is taken in and out between the FOUP connected to the load port and the load lock chamber using this wafer transfer device.

[0003]

[0004] ​In other words, the wafer is removed from one transfer point, the FOUP (Load Port), using a wafer transfer device, and transported to the other transfer point, the load lock chamber. Then, in the processing unit, the wafer transported through the load lock chamber is processed in a processing unit called a process chamber, and after processing is complete, the wafer is removed again through the load lock chamber and returned to the FOUP.

[0005] The processing unit maintains a special atmosphere, such as a vacuum, depending on the processing, to enable rapid wafer processing. Furthermore, the wafer transport chamber in the EFEM is equipped with a highly clean air atmosphere by introducing air purified through chemical filters, ensuring that the wafer surface is not contaminated by particles or other contaminants during transport. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2012-49382 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, in recent years, with increasing integration and miniaturization, concerns have arisen regarding the effects of the EFEM wafer handling chamber, which, despite its relatively high level of cleanliness, has a different air environment than that inside the FOUP or processing unit.

[0008] In other words, exposure to air makes the wafer surface susceptible to moisture and oxygen, potentially leading to corrosion and oxidation. Furthermore, if corrosive gases used in the processing equipment remain on the wafer surface, they can corrode the wiring material on the wafer surface, potentially resulting in a decrease in yield. Moreover, since the presence of moisture accelerates the corrosion reaction of corrosive elements, the presence of both corrosive gases and moisture can lead to even faster corrosion.

[0009] To avoid this, it is conceivable to create a dry nitrogen atmosphere inside the wafer transport chamber, similar to FOUP. Furthermore, depending on the type of wafer processing, a different atmosphere may be used. Alternatively, a gas atmosphere using appropriate special gases could be considered.

[0010] However, conventional EFEMs only increase the internal pressure to prevent particles from entering from the outside, and do not allow particles to enter from the outside through the wafer transport chamber and load port that make up the EFEM. Little consideration has been given to suppressing gas leakage into the EFEM. Therefore, even if special gases such as dry nitrogen are supplied to the wafer handling chamber, it is difficult to properly maintain the internal atmosphere due to gas leakage to the outside, and the cost of gas increases due to the large amount of gas required. Furthermore, if a large amount of gas leaks outside the EFEM, depending on the type of gas, it may lead to a deterioration of the working environment outside the EFEM.

[0011] The present invention aims to effectively solve these problems, and specifically aims to provide a load port and EFEM that can reduce the amount of gas used by suppressing the outflow of the gas used to the outside and the inflow from the outside, such as air, when the wafer transport chamber constituting the EFEM is in a special gas atmosphere, thereby improving the quality of the wafers. [Means for solving the problem]

[0012] To achieve this objective, the present invention employs the following means.

[0013] In other words, the load port of the present invention is provided adjacent to a wafer transport chamber and is a load port for loading and unloading wafers between the wafer transport chamber and a wafer storage container, and comprises a plate-shaped portion that forms part of the wall surface of the wafer transport chamber and has an opening formed therein for opening the wafer transport chamber, a door portion for opening and closing the opening, a mounting base on which a wafer storage container is placed and which can move back and forth toward the plate-shaped portion, with a lid portion that allows the internal space to be opened and closed facing the door portion, and an elastic material provided on the mounting base side of the plate-shaped portion along the periphery of the opening, wherein the elastic material elastically contacts the area around the lid portion of the wafer storage container when the mounting base is moved toward the plate-shaped portion.

[0014] With this configuration, by moving the wafer storage container toward the plate-shaped section together with the mounting platform, the opening of the plate-shaped section and the perimeter of the lid are connected via an elastic material. This prevents gas leakage from the wafer transport chamber to the outside, even when the lid of the wafer storage container and the door of the plate-shaped section are open. Therefore, even when the wafer transport chamber is filled with a special gas atmosphere such as an inert gas, a clean gas, or a drying gas, it is possible to reduce the amount of these gases used and thus reduce the costs required for gas management. It is also possible to suppress the deterioration of the working environment outside the wafer transport chamber due to gas leakage. Furthermore, since the inflow of gas from the outside into the wafer transport chamber can also be suppressed, it is possible to prevent particles from entering the wafer storage container and the wafer transport chamber, thereby helping to maintain wafer quality.

[0015] Even if particles are generated due to the elastic contact of the elastic material, in order to prevent these particles from entering the wafer storage container when the lid and door are opened, it is preferable to configure the wafer storage container to be equipped with a gas supply means for supplying gas into the wafer storage container via a gas supply valve provided in the wafer storage container.

[0016] In order to improve the adhesion between the wafer storage container and the elastic material and to further enhance the above-mentioned effects, it is preferable to configure the wafer storage container to include an engaging piece that can engage with a flange provided around the lid, and a retraction means for retracting the engaging piece towards the plate-like portion while it is engaged with the flange.

[0017] Furthermore, in order to suppress gas leakage from the opening regardless of whether the wafer storage container is connected or disconnected, and to further conserve gas, it is preferable to provide an elastic material along the periphery of the opening on the door side of the plate-shaped portion, and to configure the device so that when the opening is closed by the door, the elastic material provided on the door side and the door portion come into elastic contact. be.

[0018] In order to realize the above structure inexpensively, it is preferable to configure the elastic material to be an O-ring.

[0019] As an alternative structure to the above, it is also preferable that the elastic material be formed in the shape of a plate.

[0020] In order to further reduce manufacturing costs by decreasing the number of parts, it is also preferable to integrate the elastic material provided on the base side and the elastic material provided on the door side.

[0021] Furthermore, the EFEM of the present invention comprises any of the above-mentioned load ports and a housing that constitutes the wafer transport chamber, and is characterized in that a sealing member is provided between the plate-shaped portion constituting the load port and the housing.

[0022] By configuring in this way, it becomes possible to increase the sealing degree in the wafer transfer chamber and suppress the outflow of gas to the outside and the inflow of gas from the outside. Therefore, it becomes possible to easily manage the gas atmosphere in the wafer transfer chamber and reduce the cost required for management while maintaining a clean state.

[0023] Also, even when particles are generated due to the repeated elastic contact of the elastic material, in order to prevent the particles from adhering to the wafer being transferred, it is preferable to configure to form an air flow from above to below inside the wafer transfer chamber.

Effect of the Invention

[0024] According to the present invention described above, when the inside of the EFEM is set to a special gas atmosphere, it is possible to suppress the outflow of the gas used to the outside and the inflow of air or the like from the outside, reduce the supply amount of the gas used, reduce the cost, and at the same time, it is possible to provide a load port and an EFEM capable of improving the quality of the wafer.

Brief Description of the Drawings

[0025] [Figure 1] Perspective view of an EFEM equipped with a load port according to a first embodiment of the present invention. [Figure 2] Side view of the EFEM. [Figure 3] Perspective view showing a state in which a part of the load port is separated from the EFEM. [Figure 4] Perspective view of the load port. [Figure 5] Front view of the load port. [Figure 6] Rear view of the load port. [Figure 7] Side cross-sectional view of the load port. [Figure 8] Side cross-sectional view showing a state in which the FOUP is moved to the plate-like part side from the state of FIG. 7. [Figure 9]This is a side cross-sectional view showing the state in which the lid and door portion of the FOUP are separated from the plate-like portion, as in the state shown in Figure 8. [Figure 10] This is a side cross-sectional view showing the state in which the door portion of the FOUP has been moved downward along with the lid portion from the state in Figure 9. [Figure 11] This is an enlarged perspective view of the main components, showing the window unit and door section that make up the loadport device. [Figure 12] An enlarged cross-sectional view of the main part, showing an enlarged view of the AA section in Figure 11. [Figure 13] An enlarged cross-sectional view of the main part, showing an enlarged view of the BB cross-section in Figure 11. [Figure 14] An enlarged front view of the main part showing the clamp unit installed in the window unit. [Figure 15] An enlarged perspective view of the main parts, showing enlarged views of the window unit and door portion constituting the load port according to the second embodiment of the present invention. [Figure 16] Figure 15 shows an enlarged cross-sectional view of the main part of the CC cross-section. [Figure 17] An enlarged perspective view of the main parts, showing enlarged views of the window unit and door portion constituting the load port according to the third embodiment of the present invention. [Figure 18] An explanatory diagram showing a sealing member to be installed near the opening of the window unit. [Figure 19] An enlarged cross-sectional view of the main part, showing an enlarged view of the DD cross-section in Figure 17. [Figure 20] An enlarged cross-sectional view of the main part corresponding to Figure 12, showing an example of a modified load port according to the first embodiment of the present invention. [Modes for carrying out the invention]

[0026] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0027] <First Embodiment> Figure 1 shows the load port 3 of the first embodiment and the EFEM1 equipped therewith. The EFEM1 has three load ports 3 connected in a row to the front 21 which forms part of the wall surface of the wafer transport chamber 2, which is a box-shaped housing.

[0028] In this application, the direction on the side to which the load port 3 is connected, as viewed from the wafer transport chamber 2, is defined as the front, the direction on the rear surface 22 facing the front surface 21 is defined as the rear, and furthermore, the direction perpendicular to the front-rear direction and the vertical direction is defined as the side. That is, the three load ports 3 are arranged side by side along the side.

[0029] Figure 2 shows a side view of the load port 3 and the EFEM1 equipped with it. As described above, the load port 3 is connected to the front 21 of the wafer transport chamber 2. The load port 3 has a panel 31 as a plate-like part at its rear, and this panel 31 is integrated with the front 21 to form part of the wall surface of the EFEM1. The load port 3 is provided with a mounting platform 34 that extends forward from the panel 31, and a FOUP7, which serves as a wafer storage container for accommodating wafers W, can be placed on the mounting platform 34.

[0030] EFEM1 is installed on the floor surface FL, and a processing device 9 for performing predetermined processing on wafers W can be connected to its rear surface 22. A gate valve (not shown) provided on the rear surface 22 of EFEM1 allows communication between the internal space Se of the wafer transport chamber 2 and the processing device 9. A wafer transport device 8 for transporting wafers W is also provided in the internal space Se of the wafer transport chamber 2, and this wafer transport device 8 can be used to transport wafers W between the FOUP 7 installed in the load port 3 and the processing device 9.

[0031] The wafer transport chamber 2 is configured such that the internal space Se is substantially sealed when the load port 3 and processing device 9 are connected to it. It is possible to increase the nitrogen gas concentration in the internal space Se by purging with dry nitrogen gas using a gas supply port and a gas exhaust port (not shown). A fan filter unit 25 is provided at the top of the wafer transport chamber 2 to send gas downwards, a chemical filter 26 at the bottom draws the gas in, and the gas is returned to the fan filter unit 25 at the top via a circulation duct 27 located adjacent to the inside of the rear surface 22. This creates a downflow within the wafer transport chamber 2, where air flows from top to bottom, and also circulates the internal gas to maintain a clean state. Furthermore, even if particles that contaminate the surface of the wafer W are present in the internal space Se of the wafer transport chamber 2, the gas can be circulated. The Unflow mechanism pushes particles downwards, suppressing particle adhesion to the wafer W surface during transport. Furthermore, the chemical filter 26 captures residual gases from the processing device 9, allowing the internal space Se to be kept cleaner.

[0032] Figure 3 shows the state after one load port 3A has been removed from the wafer transport chamber 2 compared to the state in Figure 1. The front surface 21 to which the load port 3A is connected has an opening 23 that is slightly smaller than the panel 31 of the load port 3, and this opening 23 allows the internal space Se to be opened up. Along the periphery of the opening 23, a contact surface 24 is formed in a stepped shape that is recessed to the rear, and the rear surface of the panel 31 comes into contact with this contact surface 24.

[0033] Figures 4, 5, and 6 show a perspective view, a front view, and a rear view of the load port 3, respectively. The configuration of the load port 3 will be explained below using these figures. Note that these figures show the state in which the external cover 32 (see Figure 2), located below the mounting base 34, has been removed, exposing part of the internal structure.

[0034] The load port 3 has a panel 31 that stands vertically from behind the leg portion 35 to which casters and mounting legs are attached, and a horizontal base portion 33 is provided extending forward from a height of approximately 60% of the panel 31. Furthermore, a mounting platform 34 for placing the FOUP 7 (see Figure 2) is provided on top of this horizontal base portion 33. As schematically shown in Figure 7, the FOUP 7 consists of a main body 71 with an internal space Sf for housing wafers W (see Figure 2), and a lid portion 72 that can close an opening 71a provided on one side of the main body 71 to serve as an entrance and exit for wafers W. When correctly placed on the mounting platform 34, the lid portion 72 faces the panel 31.

[0035] Returning to Figures 4-6, the mounting base 34 is provided with a positioning pin 34a for positioning the FOUP 7, and a locking claw 34b for fixing the FOUP 7 to the mounting base 34. When the locking claw 34b performs a locking operation, it can work in cooperation with the positioning pin 34a to guide and fix the FOUP 7 to the correct position, and when it performs an unlocking operation, it can move the FOUP 7 away from the mounting base 34.

[0036] Furthermore, the mounting base 34 is equipped with two gas supply nozzles 34c, which constitute a gas supply means for supplying gas into the FOUP 7 (see Figure 2), and two gas discharge nozzles 34d, which constitute a gas discharge means for discharging gas from inside the FOUP 7. These are normally located below the upper surface of the mounting base 34, and when in use, they extend upward and connect to the gas supply valve 73 and gas discharge valve 74 (see Figure 7) of the FOUP 7, respectively. Gas purging is possible by supplying a gas such as dry nitrogen gas from the gas supply nozzle 34c to the internal space Sf (see Figure 7) of the FOUP 7 via the gas supply valve 73, and by discharging the gas from the internal space Sf through the gas discharge nozzle 34d via the gas discharge valve 74. In addition, by setting the gas supply amount to be greater than the gas discharge amount, it is possible to set a positive pressure setting in which the pressure in the internal space Sf is higher than the pressure outside and the internal space Se (see Figure 2) of the wafer transport chamber 2.

[0037] Furthermore, the mounting platform 34 can be moved in the front-to-back direction while the FOUP2 (see Figure 7) is mounted on it.

[0038] The panel 31 that makes up the load port 3 consists of support columns 31a, 31a that are erected on both sides, a panel body 31b supported by these columns, and an opening in a roughly rectangular shape on this panel body 31b. It consists of a window unit 4 attached to a window section 31c. Here, the term "approximately rectangular" in this application refers to a shape in which the four corners are smoothly connected by arcs, with a rectangle having four sides as the basic shape. A gasket 37, which is an elastic material formed in the shape of a rectangular frame, is provided near the outer circumference of the rear surface of the panel body 31b. The gasket 37 is a gas permeable... It is formed from a small amount of rubber material. The gasket 37 is positioned to contact a contact surface 24 (see Figure 3) set near the edge of the opening 23 of the wafer transport chamber 2, thereby eliminating the gap between the outer circumference of the panel body 31b and the opening 23, and suppressing gas leakage from inside the wafer transport chamber 2 to the outside.

[0039] The window unit 4 is positioned opposite the lid portion 72 (see Figure 7) of the FOUP 7 described above, and has a substantially rectangular opening 42 (see Figure 7), which will be described in detail later. This opening 42 allows the internal space Se of the wafer transport chamber 2 to be opened. The load port 3 is equipped with an opening / closing mechanism 6 for opening and closing the opening 42.

[0040] The opening / closing mechanism 6 includes a door section 61 for opening and closing the opening 42, a support frame 63 for supporting it, a movable block 65 that supports the support frame 63 so as to be movable in the front-rear direction via a slide support means 64, and a slide rail 66 that supports the movable block 65 so as to be movable in the up-down direction relative to the panel body 31b. As shown in Figure 7, the support frame 63 supports the lower rear part of the door section 61 and has a roughly crank shape that extends downward, then passes through a slit-shaped insertion hole 31d provided in the panel body 31b and protrudes toward the front of the panel body 31b. The slide support means 64, movable block 65, and slide rail 66 for supporting the support frame 63 are provided in front of the panel body 31b. In other words, the sliding parts for moving the door section 61 are outside the wafer transport chamber 2, and even if particles are generated in these parts, the small size of the insertion hole 31d, which is slit-shaped, makes it possible to suppress the entry of particles into the wafer transport chamber 2.

[0041] Furthermore, actuators (not shown) are provided for each direction to move the door section 61 in the front-to-back direction and in the up-and-down direction. By providing drive commands from the control unit Cp to these actuators, the door section 61 can be moved in the front-to-back direction and in the up-and-down direction.

[0042] Furthermore, a cover 36 is provided in front of the panel body 31b, extending downward from directly below the horizontal base 33. This cover 36 encloses the support frame 63, slide support means 64, movable block 65, and slide rail 66, creating a sealed state. Therefore, although the panel body 31b has an insertion hole 31d, gas from inside the wafer transport chamber 2 (see Figure 3) is prevented from leaking out through this hole.

[0043] The door section 61 is equipped with a latch mechanism for opening and closing the lid section 72 (see Figure 7) of the FOUP 7, and a connecting means 62 for holding the lid section 72. The connecting means 62 allows the lid section 72 to be opened by performing a latch operation, and also allows the lid section 72 to be connected to the door section 61 to form an integrated unit. Conversely, the connection between the lid section 72 and the door section can be released, and the lid section 72 can be attached to the main body 71 to form a closed state.

[0044] Here, we will explain the detailed configuration of the aforementioned window unit 4 using Figure 11. The window unit 4 consists of a window frame 41, O-rings 44 and 46 (see Figure 12) attached thereto as elastic materials, and a clamp unit 5 as a means for tightening the FOUP 7 (see Figure 7) to the window frame 41 via the O-ring 44. It is being done.

[0045] The window frame portion 41 has a frame shape with a roughly rectangular opening 42 formed on the inside. The window frame portion 41 is a component of the window unit 4 and is a part of the panel 31 (see Figure 3) described above. As such, the opening 42 can be said to open the front surface 21, which is the wall surface of the housing that constitutes the wafer transport chamber 2. The opening 42 is slightly larger than the outer circumference of the lid portion 72 (see Figure 7) of the FOUP 7, and the lid portion 72 can move through this opening 42. In addition, when the FOUP 7 is placed on the mounting base 34, the front surface of the main body 71 surrounding the lid portion 72 acts as a contact surface 71b and contacts the window frame portion 41 via the O-ring 44.

[0046] Furthermore, the door portion 61, as described above, abuts against the rear surface of the window frame portion 41 via an O-ring 46 (see Figure 12). Specifically, a thin-walled portion 61a, which is provided in a flange shape on the outer circumference of the door portion 61, abuts against it. In this case, the thick-walled portion 61b formed inside the thin-walled portion 61a is formed to be smaller than the opening 42, so that it protrudes forward through the opening 42.

[0047] Figure 12 shows an enlarged view of the AA cross-section in Figure 11. A dovetail groove 43 with a trapezoidal cross-section is formed on the front surface of the window frame 41, encircling the vicinity of the periphery of the opening 42, and an O-ring 44 is inserted inside it. Because the dovetail groove 43 has a small opening and a cross-sectional shape that widens inward, the O-ring 44 can be properly supported inside and will not easily pop out. In addition, a part of the O-ring 44 protrudes forward from the opening of the dovetail groove 43, and this protruding part can come into contact with the contact surface 71b set on the FOUP 7. Therefore, when the FOUP 7, which is placed on the mounting base 34 (see Figure 7), moves toward the panel 31 side together with the mounting base 34, the O-ring 44 can be elastically brought into contact with the contact surface.

[0048] Similarly, a dovetail groove 45 with a trapezoidal cross-section is formed on the rear surface of the window frame portion 41, encircling the vicinity of the periphery of the opening 42, and an O-ring 46 is inserted inside it. When the door portion 61 is closed, it elastically contacts the front surface of the thin-walled portion 61a on the outer circumference. The dovetail groove 45 is formed inside the dovetail groove 43, so that the wall thickness does not become extremely thin between the two, preventing insufficient strength.

[0049] Returning to Figure 11, the clamp units 5 are provided at a total of four locations on both sides of the window frame 41, spaced apart in the vertical direction. Each clamp unit 5 generally consists of an engaging piece 51 and a cylinder 52 that operates it.

[0050] Figure 13 shows an enlarged view of the BB cross-section in Figure 11. The cylinder 52 constituting the clamp unit 5 is mounted behind the window frame 41 and is equipped with a shaft 53 that can move forward and backward through a hole provided in the window frame 41. The base end 51a of the engaging piece 51 is attached to the tip of the shaft 53, and the tip 51b extends from this base end 51a toward the outer circumference of the shaft 53. In addition, a guide groove 53a is formed on the outer circumference of the shaft 53 with a 90° phase twist along the axial direction, and a guide pin 54 fixed to the window frame 41 side is inserted radially into the groove. Therefore, as the cylinder 52 moves forward and backward, the guide groove 53a is guided by the guide pin 54, and the shaft 53 rotates 90° around its axis. As shown in Figure 13b, when the engaging piece 51 is extended forward with the shaft 51, the tip 51b faces upward, and when it is retracted backward, the tip 51b faces toward the inner FOUP 7. The engaging piece 51, with its tip 51b facing inward, can engage with the flange portion 71c that protrudes laterally from the FOUP 7. While maintaining this engaged state, the shaft 53 is further pulled in by the cylinder 52, as shown in Figure 12, the FOUP 7 This makes it possible to create a clamped state in which the contact surface 71b is more tightly pressed against the O-ring 44. With four such clamping units 5 working together, the deformation of the O-ring 44 can be made uniform, further improving the sealing performance. Furthermore, when the engaging piece 51 is moved forward, the tip 51b faces upward, preventing interference with the flange portion 71c when viewed from the front. This position allows the FOUP 7 to be moved together with the mounting base 34 (see Figure 7). When the tip 51b is moved forward, it is sufficient to simply avoid interference with the flange portion 71c, and the tip 51b may be set not only to face upwards but also downwards or outwards.

[0051] Furthermore, a cable guide 55 extending in the vertical direction is provided in front of the engaging piece 51. The cable guide 55 is formed by bending sheet metal, which prevents other components from becoming entangled in the engaging piece 51. It is also preferable to fix piping, electrical wiring, etc., to the outside of this cable guide 55.

[0052] The load port 3 configured as described above operates when drive commands are issued to each part by the control unit Cp shown in Figure 4. Below, an example of operation using the load port 3 of this embodiment will be explained using Figures 7 to 10.

[0053] Figure 7 shows the FOUP 7 placed on the mounting table 34 and separated from the panel section 31. In this state, the door section 61 abuts against the rear surface of the window frame section 41 (see Figure 12) that constitutes the window unit 4 via the O-ring 46, so that no gap is created between the window frame section 41 and the door section 61, and high sealing performance can be obtained. Therefore, even if the internal space Sf of the wafer transport chamber 2 is filled with nitrogen gas or the like, the outflow of gas to the outside and the inflow of gas from the outside into the internal space Sf can be suppressed.

[0054] Although not shown in this figure, the FOUP7 is positioned and fixed to the mounting base 34 by a locking action by the locking claw 53 (see Figure 4) and a positioning action by the positioning pin 34.

[0055] Then, the gas supply nozzle 34c and gas discharge nozzle 34d of the mounting platform 34 protrude upward and are connected to the gas supply valve 73 and gas discharge valve 74 of the FOUP 7, respectively. Subsequently, fresh dry nitrogen gas is supplied from the gas supply nozzle 34c through the gas supply valve 73, and the gas that had remained in the internal space Sf is discharged from the gas supply nozzle 34c through the gas discharge valve 74. By performing this gas purging, the internal space Sf is filled with nitrogen gas and the pressure is made higher than that of the internal space Sf of the wafer transport chamber 2.

[0056] Next, as shown in Figure 8, the mounting base 34 is moved backward, and the contact surface 71b of the FOUP 7 is brought into contact with the window frame portion 41. Specifically, the contact surface 71b is brought into contact with the window frame portion 41 (see Figure 12) via the O-ring 44 provided on the front surface, thereby creating a sealed state. When moving the mounting base 34 in this manner, the engaging piece 51 (see Figure 13) is first made to protrude forward by the cylinder 52 constituting the clamp unit 5, so that the tip 51b faces upward and does not interfere with the FOUP 7.

[0057] Furthermore, by operating the connecting means 62 (see Figure 6) provided on the door portion 61, the lid portion 72 is unlatched and can be removed from the main body 71, while the door portion 61 integrally holds the lid portion 72. At the same time, the cylinder 52 constituting the clamp unit 5 pulls the engaging piece 51 (see Figure 13) backward, so that the tip 51b faces inward and engages with the flange portion 71c of the FOUP 7. By pulling it further, the contact surface 71b of the FOUP 7 is brought into closer contact with the O-ring 44, thereby improving the sealing performance. ru.

[0058] From this state, as shown in Figure 9, the door portion 61 is moved backward together with the support frame 63. This separates the lid portion 72 of the FOUP 7 from the main body 71, creating an internal space. The gap Sf can be opened. In this case, since the contact surface 71b of FOUP7 is firmly in contact with the window unit 4, it is possible to suppress the outflow and inflow of gas between the wafer transport chamber 2 and FOUP7 and the outside.

[0059] Furthermore, because the pressure in FOUP7 is high, a gas flow is generated from the internal space Sf of FOUP7 toward the wafer transport chamber 2. This suppresses the entry of particles and other contaminants from the wafer transport chamber 2 into FOUP7, making it possible to keep the inside of FOUP7 clean. In addition, continuously supplying a low flow rate of gas via the gas supply nozzle 34c is also suitable for preventing the entry of particles.

[0060] Next, the door section 61 is moved downward together with the support frame 63. This allows the rear of the opening 71a, which serves as the loading / unloading entrance for the FOUP 7, to be opened wide, making it possible to move the wafer W between the FOUP 7 and the processing unit 9 (see Figure 2). Since the mechanism for moving the door section 61 is entirely covered by the cover 36, it is possible to suppress the leakage of gas from inside the wafer transport chamber 2 to the outside.

[0061] As described above, the operation for opening the opening 71a of FOUP7 has been explained. To close the opening 71a of FOUP7, the reverse operation should be performed.

[0062] By repeatedly performing these operations, the O-rings 44 and 46 repeatedly make elastic contact with the lid 72 or door 61, which may generate new particles. When the lid 72 or door 61 is opened, these particles are moved downward by the downflow formed inside the wafer transport chamber 2 (see Figure 2). As a result, the wafer surface W does not adhere to the wafer surface W, and the wafer surface W can be kept clean.

[0063] As described above, the load port 3 in this embodiment is provided adjacent to the wafer transport chamber 2 and is for loading and unloading wafers W between the wafer transport chamber 2 and the FOUP 7, which is a wafer storage container. It comprises a panel 31 as a plate-like part that forms part of the wall surface of the wafer transport chamber 2 and has an opening 42 formed to open the inside of the wafer transport chamber 2, a door 61 for opening and closing the opening 42, a mounting base 34 on which the FOUP 7 is placed with a lid 72 that can open and close the internal space Sf facing the door 61 and which can move back and forth toward the panel 31, and an O-ring 44 as an elastic material provided on the mounting base 34 side of the panel 31 along the periphery of the opening 42. By moving the mounting base 34 toward the panel 31, the O-ring 44 elastically contacts the contact surface 71b surrounding the lid 72 of the FOUP 7.

[0064] With this configuration, by moving the FOUP 7 toward the panel 31 together with the mounting base 34, the opening 42 of the panel 31 and the area around the lid 72 are connected via the O-ring 44. This prevents gas from leaking out of the wafer transport chamber 2 to the outside, even when the lid 72 of the FOUP 7 and the door 61 on the panel 31 are opened. Therefore, even when the wafer transport chamber 2 is filled with a special gas atmosphere such as an inert gas, a cleaning gas, or a drying gas, it is possible to reduce the amount of these gases used and thus reduce the costs required for gas management. It is also possible to suppress the deterioration of the working environment outside the wafer transport chamber 2 due to gas leakage. Furthermore, since the inflow of gas from the outside into the wafer transport chamber 2 can also be suppressed, it is possible to prevent particles from entering the FOUP 7 and the wafer transport chamber 2 from the outside, thereby maintaining the quality of the wafer W.

[0065] Furthermore, since the FOUP7 is configured to also include a gas supply nozzle 34c as a gas supply means for supplying gas into the FOUP7 via a gas supply valve 73 provided in the FOUP7, even if particles are generated due to the elastic contact of the O-ring 44, the gas supply nozzle... By using 34c to raise the pressure inside FOUP7 above that inside wafer transport chamber 2, gas flows from inside FOUP7 to wafer transport chamber 2 when the lid 72 and door 61 are opened, thus preventing particles from entering FOUP7 and maintaining a clean state.

[0066] Furthermore, the FOUP 7 is equipped with an engaging piece 51 that can engage with the flange portion 71c provided around the lid portion 72, and a clamp unit 5 that acts as a retraction means for pulling the engaging piece 51 towards the panel 31 while it is engaged with the flange portion 71c. As the mounting base 34 moves, the clamp unit 5 pulls the engaging piece 51 towards the panel 31 while it is engaged with the flange portion 71c of the FOUP 7, thereby increasing the airtightness between the FOUP 7 and the O-ring 44 and further enhancing the above-mentioned effect.

[0067] Furthermore, an O-ring 46 is provided as an elastic material along the periphery of the opening 42 on the door portion 61 side of the panel 31. By closing the opening 42 with the door portion 61, the O-ring 46 on the door portion 61 side and the door portion 61 come into elastic contact. Therefore, by bringing the O-ring 46 on the door portion 61 side into elastic contact with the door portion 61, when the door portion 61 closes, gas leakage from the opening 42 can be suppressed regardless of whether the FOUP7 is connected or not, thus further saving gas.

[0068] Furthermore, since the elastic material used for sealing is O-rings 44 and 46, it is possible to construct the sealing structure inexpensively.

[0069] Furthermore, the EFEM1 of this embodiment includes the load port 3 and a housing 2 that constitutes the wafer transport chamber, with a gasket 37 as a sealing member provided between the panel 31 that constitutes the load port 3 and the housing 2. As a result, the degree of airtightness within the wafer transport chamber 2 is increased, making it possible to suppress the outflow of gas to the outside and the inflow of gas from the outside, thereby making it possible to easily manage the gas atmosphere within the wafer transport chamber 2 and reduce the costs required for management while maintaining a clean state.

[0070] In addition, since an airflow is formed inside the wafer transport chamber 2 that moves from top to bottom, even if particles are generated when the O-rings 44 and 46, which act as elastic materials, make elastic contact, the downward airflow that moves the particles downward simultaneously with the opening of the door 61 and lid 72 will prevent them from adhering to the wafer W being transported.

[0071] <Second Embodiment> Figure 15 shows the window unit 104, which constitutes part of the EFEM 101 and load port 103 of the second embodiment. The door portion 61 shown in the figure is the same as that in the first embodiment, and the parts other than the window unit 104 are configured in the same way as in the first embodiment. In this embodiment, the same reference numerals are used for the same parts as in the first embodiment, and their descriptions are omitted.

[0072] In this window unit 104, a gasket 144, which is a plate-shaped elastic material, is provided in front of the window frame portion 141 and near the periphery of the opening 142. The gasket 144 is constructed in a roughly rectangular frame shape, with the inside being the same size as the opening 142. It is fixed between the window frame portion 141 and a similarly roughly rectangular frame-shaped retaining plate 143.

[0073] Furthermore, as shown in Figure 16, a gasket 146, which is a plate-shaped elastic material configured in a roughly rectangular frame shape, is fixed to the rear surface of the window frame portion 141 using a roughly rectangular frame-shaped retaining plate 145, similar to the front surface.

[0074] The gaskets 144 and 146 are made of a rubber material with low gas permeability, and by coming into contact with the contact surface 71b of the FOUP 7 and the thin-walled portion 61a of the door portion 61, they are able to improve sealing performance.

[0075] The gaskets 144 and 146 can be designed to increase the contact area with the contact surface 71b of the FOUP 7 and the door portion 61 by appropriately changing their hardness and thickness, thereby improving their sealing performance. Therefore, it is not necessary to provide the clamp unit 5 on the window frame portion 141 as shown in the first embodiment. However, if a higher sealing performance is required, such as by increasing the pressure difference between the inside and outside, it is acceptable to provide the clamp unit 5 to improve sealing performance.

[0076] Even with the configuration described above, it is possible to obtain the same effects and advantages as those of the first embodiment described above.

[0077] Furthermore, because the elastic material used for sealing is formed in a plate shape, it is possible to construct a sealing structure at a low cost.

[0078] <Third Embodiment> Figure 17 shows a window unit 204 that constitutes part of the EFEM 201 and load port 203 of the third embodiment. The door portion 61 shown in the figure is the same as that in the first and second embodiments, and the parts other than the window unit 204 are configured in the same way as in the first embodiment. In this embodiment, the same reference numerals are used for the same parts as in the first and second embodiments, and their descriptions are omitted.

[0079] In this window unit 204, a sealing member 244, acting as an elastic member, is provided in the vicinity of the periphery of the opening 242 of the window frame portion 241, specifically so as to protrude slightly inward from the periphery of the opening 242.

[0080] The sealing member 244 has a roughly rectangular frame shape as shown in Figure 18(a), and as shown in the cross-sectional shape of Figure 18(b), a flat plate portion 244a is formed on the outer circumference, while two elastic portions 244b and 244c are formed on the inner circumference, branching in an inverted Y shape. The elastic portions 244b and 244c are shaped to protrude from the inside of the flat plate portion 244a, respectively, curving in a convex manner toward the front and rear. Due to this shape, the elastic portions 244b and 244c have a large margin of deformation and can be easily deformed in the front-rear direction.

[0081] From another perspective, the shape of the sealing member 244 described above can be described as an elastic portion 244b that protrudes forward to seal with the FOUP 7, and an elastic portion 244c that protrudes forward to seal with the door portion 61, both integrally formed via a flat plate portion 244a.

[0082] As shown in Figure 19, the sealing member 244 is fixed between the window frame portion 241 and a substantially rectangular frame-shaped stopper plate 243 provided behind it, so as to sandwich the flat plate portion 244, and the elastic portions 244b and 244c are located inside the opening 242 of the window frame portion 241.

[0083] The elastic parts 244b and 244c are able to seal by elastically contacting the contact surface 71b of the FOUP 71 and the thin-walled portion 61a of the door portion 61. In this case, since the elastic parts 244b and 244c can be greatly elastically deformed, the contact area with the contact surface 71b of the FOUP 71 and the thin-walled portion 61a of the door portion 61 can be increased and made uniform, resulting in high sealing performance. This can be achieved. Therefore, as with the second embodiment, it is not necessary to provide the clamp unit 5 shown in the first embodiment on the window frame portion 141. However, if higher sealing performance is required, it is acceptable to provide the clamp unit 5 to improve the adhesion performance.

[0084] Even with the configuration described above, it is possible to obtain the same effects and advantages as those of the first embodiment described above.

[0085] Furthermore, since the elastic material elastic part 244b provided on the mounting base 34 side for sealing and the elastic material elastic part 244c provided on the door part 61 side are integrally formed, the sealing structure can be constructed with a small number of parts, making it possible to reduce manufacturing costs.

[0086] Furthermore, the specific configuration of each part is not limited to the embodiments described above.

[0087] For example, in the above-described embodiment, the panel 31, which is a plate-like portion, was constructed by attaching the window unit 4 to the panel body portion 31b, but it is also possible to construct them as a single unit without separating them. Specifically, the window frame portion 41 that constitutes the window unit 5 may be constructed as a single unit without being separated from the panel body portion 31b.

[0088] Furthermore, in the first embodiment, an O-ring 46 was provided on the rear surface of the window frame portion 41 to seal between the window frame portion 41 and the door portion 61. However, as shown in Figure 20, the window unit 304 and the door portion 361 may be modified. That is, instead of the rear surface of the window frame portion 341, a dovetail groove 345 may be formed in the thin-walled portion 361a of the door portion 361, and the O-ring 346 may be inserted into the groove. Even in this case, the same sealing performance can be obtained by bringing the thin-walled portion 361a of the door portion 361 and the rear surface of the window frame portion 341 into contact via the O-ring 346.

[0089] Furthermore, in the above-described embodiment, the gas supply nozzle 34c, which is a gas supply means, was incorporated into the mounting base 34, and the system was configured as a so-called bottom purge method in which gas is supplied into the FOUP 7 from below. However, the gas supply nozzle 34c may also be incorporated into the door section 61, and the system may be configured as a so-called front purge method in which gas is supplied into the FOUP 7 from the front. In addition, even if the load port 3 does not have a gas supply means, it is possible to obtain effects similar to those described above by using a gas supply device to the FOUP 3 that is configured separately from the load port 3, such as a so-called purge station, and installing the load port 3 in a state where gas has been supplied into the FOUP 7 in advance to increase the pressure.

[0090] Furthermore, in the above-described embodiment, nitrogen gas was used as the gas supplied to the EFEM1 and FOUP7, but various other gases such as air and ozone can be used depending on the processing.

[0091] Furthermore, although FOUP7 was used as the wafer storage container in the above embodiment, the same configuration can be used when using other types of wafer storage containers, and the same effects as described above can be obtained.

[0092] Other configurations can also be modified in various ways without departing from the spirit of the present invention. [Explanation of Symbols]

[0093] 1…EFEM 2…Wafer transport room (enclosure) 3…Load port 5… Clamp unit (retraction mechanism) 7…FOUP (Wafer Storage Container) 31... Panel (plate-shaped part) 34… Mounting platform 34c... Gas supply nozzle (gas supply means) 37…Gasket (sealing material) 42...Aperture 44, 46… O-ring (elastic material) 51…Engaging piece 61... Door section 71c…Tsubabe 72…Lid part 73... Gas supply valve 144,146… Gasket (elastic material) 244b, 244c... Elastic parts (elastic materials) W...wafer

Claims

[Claim 1] A plate-shaped portion having an opening formed to open the wafer transport chamber, A door section for opening and closing the aforementioned opening, A mounting platform on which the wafer storage container is placed, with a lid portion that allows the internal space of the wafer storage container to be opened and closed facing the door portion, and which allows the wafer storage container to move back and forth toward the plate-shaped portion, A load port comprising: a clamp unit that engages with a flange provided on the wafer storage container and pulls the flange towards the plate-shaped portion, The clamping unit is The wafer storage container has an engaging piece that can engage with a flange provided around the lid, It comprises a cylinder that can move forward and backward to operate the engaging piece, The load port is characterized in that the engaging piece rotates in conjunction with the reciprocating movement of the cylinder and engages with the flange.

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