Load port and drive method of the same

Abstract

To provide a load port which enables improvement of sealability in an EFEM and achieves reduction of a supply amount of a gas used in the EFEM and improvement of the quality of a wafer.SOLUTION: A load port is provided adjacent to a wafer transport chamber and used to carry a wafer into / out between the wafer transport chamber and a front-opening unified pod (FOUP). The load port includes: a panel which forms a part of a wall surface of the wafer transport chamber and is formed with an opening for opening the wafer transport chamber; a door part for opening and closing the opening; a placement platform on which the FOUP is placed so that a lid part, which may open or close an internal space, faces the door part and which may move forward to or backward from the panel; and an O ring provided along a peripheral edge of the opening.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a load port that can reduce the amount of gas used even when a special gas atmosphere is created inside a wafer transfer chamber, and an EFEM equipped with the load port. [Background technology]

[0002] Conventionally, semiconductors have been manufactured by subjecting wafers to various processing steps. In recent years, the integration of elements and the miniaturization of circuits have progressed more and more, and it is necessary to keep the area around the wafers highly clean so that particles and moisture do not adhere to the wafer surface. Furthermore, in order to prevent the wafer surface from being oxidized or otherwise changed in surface properties, the wafer is surrounded by an inert nitrogen atmosphere or a vacuum.

[0003] In order to properly maintain the atmosphere around the wafers, the wafers are stored in a sealed storage pod called a FOUP (Front-Opening Unified Pod), which is filled with nitrogen. Furthermore, an Equipment Front End Module (EFEM) as disclosed in the following Patent Document 1 is used to transfer the wafers between a processing device that processes the wafers and the FOUP. The EFEM forms a wafer transfer chamber that is substantially closed inside a housing, and has a load port on one of its opposing walls that functions as an interface with the FOUP, and is connected to a load lock chamber, which is a part of the processing device, on the other side. A wafer transfer device for transferring the wafers is provided in the wafer transfer chamber, and the wafers are inserted and removed between the FOUP connected to the load port and the load lock chamber using the wafer transfer device.

[0004] That is, the wafer is removed from one transfer position, a FOUP (load port), by a wafer transfer device and transferred to the other transfer position, a load lock chamber. In the processing device, the wafer transferred through the load lock chamber is processed in a processing unit called a process chamber, and after the processing is completed, the wafer is removed again through the load lock chamber and returned to the FOUP.

[0005] The inside of the processing equipment is kept in a special atmosphere such as a vacuum depending on the processing so that the processing of the wafer can be performed quickly. Also, the inside of the wafer transfer chamber in the EFEM is kept in a highly clean air atmosphere by introducing purified air through a chemical filter, etc., so that the surface of the wafer is not contaminated by the adhesion of particles during transfer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2012-49382 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in recent years, with the trend toward ever-increasing integration and miniaturization, concerns have arisen about the effects of the air atmosphere inside the EFEM wafer transfer chamber being different from that inside FOUPs and processing equipment, even though the level of cleanliness inside the chamber is relatively high.

[0008] That is, exposure to air atmosphere can easily cause moisture and oxygen to adhere to the wafer surface, which can lead to corrosion and oxidation. In addition, if corrosive gases used in processing equipment remain on the wafer surface, they can corrode the wiring material on the wafer surface, resulting in a decrease in yield. Furthermore, since corrosive elements accelerate the corrosion reaction in the presence of moisture, the presence of both corrosive gases and moisture can cause corrosion to proceed more quickly.

[0009] To avoid this, it is possible to use a dry nitrogen atmosphere inside the wafer transfer chamber, just like in the FOUP. Furthermore, other atmospheres besides dry nitrogen may be used depending on the processing of the wafers. In some cases, it may be possible to use a gas atmosphere containing a special gas.

[0010] However, in conventional EFEM, the internal pressure is only increased to prevent particles from entering from the outside, and the external pressure is limited to the wafer transfer chamber and load port that make up the EFEM. There is little consideration given to preventing gas leakage into the EFEM. Therefore, even if special gases such as dry nitrogen are supplied into the wafer transfer chamber, it is difficult to properly maintain and manage the atmosphere inside the chamber due to the gas leaking out, and the cost of gas increases because a large amount of gas is required. Furthermore, if a large amount of gas leaks out of the EFEM, it may lead to a deterioration of the work environment outside the EFEM depending on the type of gas.

[0011] The present invention has an object to effectively solve these problems, and specifically, an object of the present invention is to provide a load port and EFEM that, when a special gas atmosphere is created inside the wafer transfer chamber that constitutes the EFEM, can reduce the amount of gas supplied by suppressing the outflow of the gas used to the outside and the inflow of air, etc. from the outside, thereby reducing the amount of gas used and improving the quality of the wafers. [Means for solving the problem]

[0012] In order to achieve the above object, the present invention takes the following measures.

[0013] In other words, the load port of the present invention is a load port provided adjacent to a wafer transport chamber for loading and unloading wafers between the wafer transport chamber and a wafer storage container, and is characterized in that it comprises a plate-shaped portion that forms part of the wall of the wafer transport chamber and has an opening formed therein for opening the inside of the wafer transport chamber, a door portion for opening and closing the opening, a mounting table on which a wafer storage container is placed so that a lid portion that can open and close the internal space faces the door portion and which can be moved forward and backward toward the plate-shaped portion, and an elastic material provided on the mounting table side of the plate-shaped portion along the periphery of the opening, and is configured so that the elastic material elastically contacts the periphery of the lid portion of the wafer storage container by moving the mounting table toward the plate-shaped portion.

[0014] With this configuration, by moving the wafer storage container together with the mounting table toward the plate-shaped part, the opening of the plate-shaped part and the periphery of the lid are connected via an elastic material, and even when the lid of the wafer storage container and the door of the plate-shaped part are opened, it is possible to prevent gas from leaking out of the wafer transfer chamber to the outside. Therefore, even when the wafer transfer chamber is filled with a special gas atmosphere such as an inert gas, clean gas, or dry gas, it is possible to reduce the amount of gas used and reduce the cost required for gas management, and it is also possible to prevent the deterioration of the working environment outside the wafer transfer chamber due to gas leakage. Furthermore, since the inflow of gas from the outside into the wafer transfer chamber can be prevented, it is also possible to prevent particles from entering the wafer storage container or the wafer transfer chamber, and it is also possible to maintain the quality of the wafers.

[0015] In order to prevent particles from entering the wafer storage container when the lid and door are opened even if particles are generated due to the elastic contact of the elastic material, and to make it possible to increase the pressure inside the wafer storage container higher than that inside the wafer transport chamber, it is preferable to configure the wafer storage container 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 further enhance the above-mentioned effect, it is preferable to configure the wafer storage container to include an engagement piece that can engage with a flange portion provided around the lid portion, and a retraction means that retracts the engagement piece toward the plate-shaped portion while engaged with the flange portion.

[0017] In order to suppress the outflow of gas from the opening regardless of whether the wafer storage container is connected or not and to further save gas, it is preferable to further provide an elastic material provided on the door portion side of the plate-shaped part along the periphery of the opening, and to configure the door portion so that the elastic material provided on the door portion side and the door portion elastically come into contact with each other by closing the opening with the door portion. be.

[0018] In order to realize the above structure at low cost, it is preferable that the elastic member is an O-ring.

[0019] As a structure different from the above, it is also preferable to configure the elastic material in a plate shape.

[0020] In order to reduce the number of parts and further reduce manufacturing costs, it is also preferable that the elastic material provided on the mounting table side and the elastic material provided on the door portion side are integrally formed.

[0021] The EFEM of the present invention includes any one of the load ports described above and a housing that constitutes the wafer transfer chamber, and is characterized in that a seal member is provided between a plate-like portion that constitutes the load port and the housing.

[0022] With this configuration, it is possible to increase the degree of sealing inside the wafer transfer chamber and suppress gas from leaking out to the outside or gas from the outside from coming in. This makes it possible to easily manage the gas atmosphere inside the wafer transfer chamber and reduce the costs required for management while maintaining a clean state.

[0023] Furthermore, even if particles are generated due to repeated elastic contact of the elastic material, in order to prevent the particles from adhering to the wafer being transported, it is preferable to configure the wafer transport chamber so that an air current flows from above to below. Effect of the Invention

[0024] According to the present invention as described above, when a special gas atmosphere is created inside the EFEM, it is possible to provide a load port and EFEM which can reduce the amount of gas used by suppressing the outflow of the gas to the outside and the inflow of air or the like from the outside, thereby reducing costs by reducing the supply of gas used and improving wafer quality. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a perspective view of an EFEM equipped with a load port according to a first embodiment of the present invention. [Diagram 2] Side view of the EFEM. [Diagram 3] FIG. 2 is a perspective view showing the EFEM with some of the load ports separated. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] 8 is a side cross-sectional view showing a state in which the FOUP has been moved toward the plate-shaped portion from the state shown in FIG. 7; [Figure 9]9 is a side cross-sectional view showing a state in which the door portion together with the lid portion of the FOUP has been separated from the plate-shaped portion from the state shown in FIG. 8 . [Figure 10] 10 is a side cross-sectional view showing a state in which the door portion has been moved downward together with the lid portion of the FOUP from the state shown in FIG. 9 . [Figure 11] FIG. 2 is an enlarged perspective view of a main portion of a window unit and a door portion that constitute the load port apparatus; [Figure 12] 12 is an enlarged cross-sectional view of a main portion taken along line AA in FIG. 11. [Figure 13] 12 is an enlarged cross-sectional view of a main part showing a cross section BB in FIG. 11 . [Figure 14] FIG. 4 is an enlarged front view of a main portion showing a clamp unit provided in the window unit. [Figure 15] FIG. 7 is an enlarged perspective view of a main portion showing a window unit and a door portion that configure a load port according to a second embodiment of the present invention. [Figure 16] 16 is an enlarged cross-sectional view of a main portion showing a cross section CC in FIG. 15 . [Figure 17] FIG. 11 is an enlarged perspective view of a main portion showing a window unit and a door portion that configure a load port according to a third embodiment of the present invention. [Figure 18] FIG. 4 is an explanatory diagram showing a seal member attached in the vicinity of the opening of the window unit. [Figure 19] 18 is an enlarged cross-sectional view of a main portion taken along line DD in FIG. 17. [Figure 20] 13 is an enlarged cross-sectional view of a main portion corresponding to FIG. 12 and showing a modified example of the load port according to the first embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0027] First Embodiment The load port 3 of the first embodiment and the EFEM 1 equipped with the same are shown in Fig. 1. The EFEM 1 has three load ports 3 connected in a row to a front surface 21 that constitutes part of the wall of the wafer transfer chamber 2 that forms a box-shaped housing.

[0028] In this application, the direction toward the side to which the load port 3 is connected as viewed from the wafer transfer chamber 2 is defined as the front, the direction toward the rear surface 22 side opposite the front surface 21 is defined as the rear, and further, the direction perpendicular to the front-rear direction and the vertical direction is defined as the side. In other words, the three load ports 3 are arranged side by side.

[0029] 2 is a side view of the load port 3 and the EFEM 1 equipped with the same. As described above, the load port 3 is connected to the front surface 21 of the wafer transfer chamber 2. The load port 3 has a panel 31 as a plate-shaped part at the rear, and this panel 31 is integrated with the front surface 21 to form part of the wall of the EFEM 1. The load port 3 is provided with a mounting table 34 that protrudes forward from the panel 31, and it is possible to place a FOUP 7, which serves as a wafer storage container for accommodating wafers W, on the mounting table 34.

[0030] The EFEM 1 is installed on a floor surface FL, and a processing device 9 for performing a predetermined process on the wafer W can be connected to the rear surface 22 side, and the internal space Se of the wafer transfer chamber 2 and the processing device 9 are communicated with each other via a gate valve (not shown) provided on the rear surface 22 of the EFEM 1. A wafer transfer device 8 for transferring the wafer W is provided in the internal space Se of the wafer transfer chamber 2, and the wafer transfer device 8 can be used to transfer the wafer W between the FOUP 7 installed on the load port 3 and the processing device 9.

[0031] The wafer transfer chamber 2 is configured so that the internal space Se is substantially sealed by connecting the load port 3 and the processing device 9, and 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 transfer chamber 2 to send gas downward, and the gas is sucked by a chemical filter 26 provided at the bottom, and the gas is returned to the upper fan filter unit 25 through a circulation duct 27 provided adjacent to the inside of the rear surface 22. In this way, a downflow, which is an air current from above to below, is formed in the wafer transfer chamber 2, and the internal gas is circulated to maintain a clean state. Even if particles that contaminate the surface of the wafer W are present in the internal space Se of the wafer transfer chamber 2, the downflow is prevented. The downflow pushes down particles, making it possible to suppress adhesion of particles to the surface of the wafer W during transportation. In addition, the chemical filter 26 can capture residual gas from the processing device 9, making it possible to keep the internal space Se in a cleaner state.

[0032] 3 shows a state in which one load port 3A has been removed from the wafer transfer chamber 2 from the state shown in FIG. 1. An opening 23 that is slightly smaller than the panel 31 of the load port 3 is provided on the front surface 21 to which the load port 3A is connected, and this opening 23 makes it possible to open up the internal space Se. Along the periphery of the opening 23, an abutment surface 24 is formed in a stepped shape recessed toward the rear, and the rear surface of the panel 31 abuts against this abutment surface 24.

[0033] 4, 5, and 6 respectively show a perspective view, a front view as seen from the front, and a rear view as seen from the rear of the load port 3. The configuration of the load port 3 will be explained below using these drawings. Note that these drawings show a state in which the external cover 32 (see FIG. 2) located below the mounting table 34 has been removed to expose part of the internal structure.

[0034] In the load port 3, a panel 31 is vertically erected from the rear of legs 35 to which casters and installation legs are attached, and a horizontal base 33 is provided facing forward from a position at about 60% of the height of the panel 31. Furthermore, a mounting table 34 for mounting a FOUP 7 (see FIG. 2) is provided on the upper part of the horizontal base 33. As shown typically in FIG. 7, the FOUP 7 is composed of a main body 71 having an internal space Sf for accommodating a wafer W (see FIG. 2), and a lid 72 capable of closing an opening 71a provided on one side of the main body 71 to serve as an entrance for loading and unloading the wafer W. When the FOUP 7 is properly mounted on the mounting table 34, the lid 72 faces the panel 31.

[0035] 4 to 6, positioning pins 34a for positioning the FOUP 7 are provided on the mounting table 34, and locking claws 34b for fixing the FOUP 7 to the mounting table 34 are also provided. By performing a locking operation, the locking claws 34b can cooperate with the positioning pins 34a to guide and fix the FOUP 7 to an appropriate position, and by performing an unlocking operation, the FOUP 7 can be made removable from the mounting table 34.

[0036] The mounting table 34 is provided with two gas supply nozzles 34c constituting a gas supply means for supplying gas into the FOUP 7 (see FIG. 2) and two gas exhaust nozzles 34d constituting a gas exhaust means for exhausting gas from the inside of the FOUP 7. These are usually located below the upper surface of the mounting table 34, and when in use, they move upward to connect to a gas supply valve 73 and a gas exhaust valve 74 (see FIG. 7) of the FOUP 7. Gas such as dry nitrogen gas is supplied from the gas supply nozzle 34c via the gas supply valve 73 to the internal space Sf of the FOUP 7 (see FIG. 7), and gas in the internal space Sf is exhausted from the gas exhaust nozzle 34d via the gas exhaust valve 74, thereby enabling gas purging. By making the gas supply amount larger than the gas exhaust amount, the pressure in the internal space Sf can be set to a positive pressure higher than the pressure of the outside and the internal space Se of the wafer transfer chamber 2 (see FIG. 2).

[0037] Furthermore, the placement stage 34 is capable of moving in the front-rear direction with the FOUP 2 (see FIG. 7) placed thereon.

[0038] The panel 31 constituting the load port 3 is made up of support columns 31a, 31a standing on both sides, a panel body 31b supported by these support columns, and a substantially rectangular opening on the panel body 31b. The panel body 31b is made up of a window unit 4 attached to a window portion 31c that is formed by a rectangular frame. In this application, the term "approximately rectangular" refers to a shape having a four-sided rectangle as a basic shape, with the four corners smoothly connected by arcs. A gasket 37 is provided near the outer periphery of the rear surface of the panel body 31b as an elastic material formed in a rectangular frame shape. The gasket 37 is provided to prevent gas permeation. The gasket 37 is made of a small amount of rubber material. The gasket 37 is adapted to come into contact with the contact surface 24 (see FIG. 3) set near the edge of the opening 23 of the wafer transfer chamber 2 described above, and eliminates a gap between the outer periphery of the panel body 31b and the opening 23, thereby suppressing gas leakage from inside the wafer transfer chamber 2 to the outside.

[0039] The window unit 4 is provided at a position facing the lid 72 (see FIG. 7) of the above-mentioned FOUP 7, and is provided with a substantially rectangular opening 42 (see FIG. 7) as described in detail later, so that the internal space Se of the wafer transfer chamber 2 can be opened through this opening 42. The load port 3 is provided with an opening / closing mechanism 6 for opening and closing the opening 42.

[0040] The opening / closing mechanism 6 includes a door portion 61 for opening and closing the opening 42, a support frame 63 for supporting the door portion 61, a movable block 65 for supporting the support frame 63 via a slide support means 64 so as to be movable in the front-rear direction, and a slide rail 66 for supporting the movable block 65 so as to be movable in the up-down direction with respect to the panel body 31b. As shown in FIG. 7, the support frame 63 supports the rear lower portion of the door portion 61, and has a generally crank-like shape that extends downward and 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, the movable block 65, and the slide rail 66 for supporting the support frame 63 are provided in front of the panel body 31b. That is, the sliding parts for moving the door portion 61 are located outside the wafer transfer chamber 2, and even if particles are generated in these parts, the insertion hole 31d is made small in a slit shape, so that it is possible to suppress the particles from entering the wafer transfer chamber 2.

[0041] Furthermore, actuators (not shown) for moving the door portion 61 in the forward / backward and upward / downward directions are provided for each direction, and by giving these actuators drive commands from the control unit Cp, the door portion 61 can be moved in the forward / backward and upward / downward directions.

[0042] Further, a cover 36 is provided in front of the panel main body 31b, extending downward from directly below the horizontal base 33, and the support frame 63, slide support means 64, movable block 65 and slide rail 66 are covered and sealed inside this cover 36. Therefore, although an insertion hole 31d is formed in the panel main body 31b, gas in the wafer transfer chamber 2 (see FIG. 3) is prevented from leaking out through this portion.

[0043] The door section 61 is equipped with a connecting means 62 for performing a latch operation for opening and closing the lid section 72 (see FIG. 7) of the FOUP 7 and for holding the lid section 72. With this connecting means 62, the lid section 72 can be put into an openable state by performing a latch operation on the lid section 72, and the lid section 72 can be connected to the door section 61 to be in an integrated state. 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 be in a closed state.

[0044] Here, the detailed configuration of the window unit 4 described above will be described with reference to Fig. 11. The window unit 4 is composed of a window frame portion 41, O-rings 44, 46 (see Fig. 12) as elastic members attached thereto, and a clamp unit 5 as a pulling means for tightly contacting the FOUP 7 (see Fig. 7) with the window frame portion 41 via the O-ring 44. It has been done.

[0045] The window frame portion 41 is in the shape of a frame with a substantially rectangular opening 42 formed on the inside. The window frame portion 41 is formed by forming a part of the panel 31 (see FIG. 3) described above as a component of the window unit 4. Since the opening 42 constitutes the casing, it can be said that the opening 42 opens the front surface 21 which serves as a wall surface of the housing which constitutes the wafer transfer chamber 2. The opening 42 is slightly larger than the outer periphery of the lid portion 72 (see FIG. 7) of the FOUP 7, and the lid portion 72 can move through the opening 42. In addition, when the FOUP 7 is placed on the placement table 34, the front surface of the main body 71 which surrounds the lid portion 72 abuts against the window frame portion 41 via the O-ring 44 as a contact surface 71b.

[0046] The door portion 61 described above abuts against the rear surface of the window frame portion 41 via the O-ring 46 (see FIG. 12). Specifically, a thin portion 61a provided in a brim shape on the outer periphery of the door portion 61 abuts against it. At this time, a thick portion 61b formed inside the thin portion 61a is formed smaller than the opening 42, so that it protrudes forward through the opening 42.

[0047] FIG. 12 is an enlarged view of the AA cross section in FIG. 11. A dovetail groove 43 having a trapezoidal cross section is formed on the front surface of the window frame portion 41 so as to go around the periphery of the opening 42, and an O-ring 44 is inserted inside the dovetail groove 43. The dovetail groove 43 has a small opening and a cross-sectional shape that widens toward the inside, so that the O-ring 44 can be properly supported inside and the O-ring 44 does 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 abut against the abutment surface 71b set on the FOUP 7. Therefore, when the FOUP 7 placed on the placement table 34 (see FIG. 7) moves toward the panel 31 together with the placement table 34, the O-ring 44 can be elastically abutted against the abutment surface.

[0048] Similarly, a dovetail groove 45 with a trapezoidal cross section is formed around the periphery of the opening 42 on the rear surface of the window frame 41, and an O-ring 46 is inserted inside the dovetail groove 45. When the door 61 is closed, the dovetail groove 45 comes into elastic contact with the front surface of the thin-walled portion 61a on the outer periphery. The dovetail groove 45 is formed inside the dovetail groove 43, so that the thickness between the two does not become too thin, which would cause a lack of strength.

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

[0050] FIG. 13 is an enlarged view of the BB cross section in FIG. 11. The cylinder 52 constituting the clamp unit 5 is attached to the rear of the window frame 41, and is provided with a shaft 53 that can be advanced and retreated forward through a hole provided in the window frame 41. The base end 51a of the engagement piece 51 is attached to the tip of the shaft 53, and the tip 51b extends from the base end 51a toward the outer periphery of the shaft 53. In addition, a guide groove 53a twisted by 90 degrees along the axial direction is formed on the outer periphery of the shaft 53, and a guide pin 54 fixed to the window frame 41 side is inserted radially into the guide groove 53a. Therefore, the guide pin 54 guides the guide groove 53a with the advancement and retreat of the cylinder 52, and the shaft 53 rotates 90 degrees around the axis. Then, as shown in FIG. 13b, when the engagement piece 51 jumps out forward together with the shaft 51, the tip 51b faces upward, and when the engagement piece 51 is retracted backward, the tip 51b faces the inner FOUP 7. The engaging piece 51 has a tip 51b facing inward, so that it can engage with a flange 71c that protrudes laterally from the FOUP 7. While maintaining this engaged state, the shaft 53 is further retracted by the cylinder 52, so that the FOUP 7 is pulled outward as shown in FIG. It is possible to clamp the contact surface 71b against the O-ring 44 with even greater tightness. By using such clamp unit 5 at four points, the amount of deformation of the O-ring 44 can be made uniform, and the sealing performance can be improved. When the engagement piece 51 is moved forward, the tip 51b faces upward, and does not interfere with the flange 71c when viewed from the front. In this way, the FOUP 7 can be moved together with the placement table 34 (see FIG. 7). When the tip 51b is moved forward, it is only necessary to avoid interference with the flange 71c, and the tip 51b may be set not only upward but also downward or outward.

[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 made of bendable sheet metal, and can prevent other members from getting entangled in the engaging piece 51. It is also preferable to fix pipes, electrical wiring, etc. to the outside of this cable guide 55.

[0052] The load port 3 configured as described above is operated by the control unit Cp shown in Fig. 4 giving drive commands to each unit. An operation example when the load port 3 of this embodiment is used will be described below with reference to Figs. 7 to 10.

[0053] 7 shows a state in which a FOUP 7 is placed on the placement table 34 and separated from the panel portion 31. In this state, the door portion 61 abuts against the rear surface of the window frame portion 41 (see FIG. 12) constituting the window unit 4 via the O-ring 46, so that no gap is generated between the window frame portion 41 and the door portion 61, and high sealing performance can be obtained. Therefore, even if the internal space Sf of the wafer transfer chamber 2 is filled with nitrogen gas or the like, it is possible to suppress the outflow of gas to the outside and the inflow of gas from the outside into the internal space Sf.

[0054] Although not shown in this figure, the FOUP 7 is fixed at an appropriate position relative to the placement table 34 by the locking action of the locking claws 53 (see FIG. 4) and the positioning action of the positioning pins 34.

[0055] Then, the gas supply nozzle 34c and the gas exhaust nozzle 34d of the mounting table 34 protrude upward and are connected to the gas supply valve 73 and the gas exhaust valve 74 of the FOUP 7, respectively. After that, 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 until then is exhausted from the gas supply nozzle 34c through the gas exhaust valve 74. By performing gas purging in this manner, the internal space Sf is filled with nitrogen gas and the pressure therein is made higher than that of the internal space Sf of the wafer transfer chamber 2.

[0056] 8, the mounting table 34 is moved rearward to bring the abutment surface 71b of the FOUP 7 into contact with the window frame portion 41. Specifically, the abutment surface 71b is brought into contact with the window frame portion 41 (see FIG. 12) via the O-ring 44 provided on the front surface of the window frame portion 41, thereby creating a sealed state. When moving the mounting table 34 in this manner, the engagement piece 51 (see FIG. 13) is caused to protrude forward in advance by the cylinder 52 constituting the clamp unit 5, and the tip 51b is set in an upward direction so as not to interfere with the FOUP 7.

[0057] Furthermore, by operating the connecting means 62 (see FIG. 6) provided on the door portion 61, the lid portion 72 is put into an unlatched state, making it removable from the main body 71, and the lid portion 72 is held integrally by the door portion 61. At the same time, the engaging piece 51 (see FIG. 13) constituting the clamp unit 5 is pulled backward by the cylinder 52, so that the tip 51b faces inward and engages with the flange portion 71c of the FOUP 7, and by further pulling it in, the abutment surface 71b of the FOUP 7 is brought into closer contact with the O-ring 44, improving the sealing performance. do.

[0058] 9, the door portion 61 is moved rearward together with the support frame 63. In this way, the lid portion 72 of the FOUP 7 is separated from the body 71, and the internal space is opened. At this time, since the contact surface 71b of the FOUP 7 is firmly in contact with the window unit 4, it is possible to suppress the outflow or inflow of gas between the wafer transfer chamber 2 and the FOUP 7 and the outside.

[0059] In addition, since the pressure in the FOUP 7 is high, a gas flow is generated from the internal space Sf of the FOUP 7 toward the inside of the wafer transfer chamber 2. This makes it possible to prevent particles and the like from entering the FOUP 7 from the wafer transfer chamber 2, and to keep the inside of the FOUP 7 clean. Note that 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 portion 61 is moved downward together with the support frame 63. This allows the rear of the opening 71a serving as the loading / unloading entrance of the FOUP 7 to be widely opened, making it possible to transfer the wafers W between the FOUP 7 and the processing device 9 (see FIG. 2). Since the mechanism for moving the door portion 61 in this manner is entirely covered by the cover 36, it is possible to prevent gas from leaking out of the wafer transfer chamber 2.

[0061] As described above, the operations for opening the opening 71a of the FOUP 7 have been described. To close the opening 71a of the FOUP 7, the operations described above may be performed in reverse.

[0062] By repeating such an operation, the O-rings 44, 46 are repeatedly elastically contacted with the lid part 72 or the door part 61, and new particles may be generated. Such particles are moved downward by the downflow formed inside the wafer transfer chamber 2 when the lid part 72 or the door part 61 is opened (see FIG. 2). Therefore, the particles do not adhere to the surface of the wafer W, and the surface of the wafer W can be maintained in a clean state.

[0063] As described above, the load port 3 in this embodiment is provided adjacent to the wafer transfer chamber 2 and is used to transfer wafers W between the wafer transfer chamber 2 and the FOUP 7, which is a wafer storage container. The load port 3 comprises the panel 31 as a plate-shaped portion that constitutes part of the wall of the wafer transfer chamber 2 and has the opening 42 formed therein for opening the interior of the wafer transfer chamber 2, the door portion 61 for opening and closing the opening 42, the mounting table 34 on which the FOUP 7 is placed so that the lid portion 72 that can open and close the internal space Sf faces the door portion 61 and the FOUP 7 can be moved forward and backward toward the panel 31, and the O-ring 44 as an elastic material that is provided on the mounting table 34 side of the panel 31 along the periphery of the opening 42. The O-ring 44 is configured to elastically contact the abutment surface 71b that forms the periphery of the lid portion 72 of the FOUP 7 by moving the mounting table 34 toward the panel 31.

[0064] With this configuration, by moving the FOUP 7 together with the mounting table 34 toward the panel 31, the opening 42 of the panel 31 and the periphery of the cover 72 are connected via the O-ring 44, and even when the cover 72 of the FOUP 7 and the door 61 provided on the panel 31 are opened, it is possible to prevent gas from leaking out of the wafer transfer chamber 2 to the outside. Therefore, even when the inside of the wafer transfer chamber 2 is made to have a special gas atmosphere such as an inert gas, clean gas, or dry gas, it is possible to reduce the amount of gas used and reduce the cost required for gas management, and it is also possible to prevent the deterioration of the working environment outside the wafer transfer chamber 2 due to the leak of gas. Furthermore, since the inflow of gas from the outside into the wafer transfer chamber 2 can also be prevented, it is possible to prevent particles from entering the FOUP 7 or the wafer transfer chamber 2 from the outside, and it is also possible to maintain the quality of the wafers W.

[0065] In addition, the gas supply nozzle 34c is further provided as a gas supply means for supplying gas into the FOUP 7 via the gas supply valve 73 provided in the FOUP 7. Therefore, even if particles are generated due to the elastic contact of the O-ring 44, the gas supply nozzle 34c can be used to supply gas into the FOUP 7. By using valve 34c to make the pressure inside FOUP 7 higher than that inside wafer transfer chamber 2, gas will flow from inside FOUP 7 to the wafer transfer chamber 2 when lid 72 and door 61 are opened, making it possible to prevent particles from entering FOUP 7 and maintain a clean state.

[0066] Furthermore, the FOUP 7 is equipped with an engagement piece 51 that can engage with a flange portion 71c provided around the lid portion 72, and a clamp unit 5 as a retracting means for retracting the engagement piece 51 toward the panel 31 while it is engaged with the flange portion 71c. As the mounting table 34 moves, the engagement piece 51 is retracted toward the panel 31 while engaged with the flange portion 71c of the FOUP 7 by the clamp unit 5, thereby improving the adhesion between the FOUP 7 and the O-ring 44 and further enhancing the above-mentioned effect.

[0067] In addition, an O-ring 46 is further provided as an elastic material provided on the door portion 61 side of the panel 31 along the periphery of the opening 42, and is configured so that the O-ring 46 provided on the door portion 61 side and the door portion 61 come into elastic contact when the opening 42 is closed by the door portion 61. Therefore, by making the O-ring 46 provided on the door portion 61 side come into elastic contact with the door portion 61, when the door portion 61 is closed, it is possible to suppress the outflow of gas from the opening 42 regardless of whether the FOUP 7 is connected or not, thereby further saving gas.

[0068] Furthermore, since the elastic material for sealing is the O-rings 44 and 46, the seal structure can be constructed at low cost.

[0069] Furthermore, the EFEM 1 of this embodiment includes the load port 3 and the housing 2 that constitutes the wafer transfer chamber, and a gasket 37 is provided as a seal member between the panel 31 that constitutes the load port 3 and the housing 2. Therefore, it is possible to increase the airtightness inside the wafer transfer chamber 2 and suppress the outflow of gas to the outside and the inflow of gas from the outside, and it is possible to easily manage the gas atmosphere inside the wafer transfer chamber 2 and reduce the cost required for management while maintaining a clean state.

[0070] In addition, since an air current flowing from above to below is formed inside the wafer transport chamber 2, even if particles are generated due to the elastic contact of the O-rings 44, 46 as elastic materials, the particles can be moved downward by the downward air current at the same time as the door portion 61 or the lid portion 72 is opened, so that the particles do not adhere to the wafer W being transported.

[0071] <Second embodiment> 15 shows a window unit 104 that 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 other than the window unit 104, the second embodiment is configured in the same way as the first embodiment. In this embodiment, the same parts as those in the first embodiment are given the same reference numerals, and the description will be omitted.

[0072] In this window unit 104, a gasket 144 as a plate-shaped elastic material is provided in a portion in front of the window frame portion 141 and in the vicinity of the periphery of the opening 142. The gasket 144 is configured in a substantially rectangular frame shape, with the inside being the same size as the opening 142. The gasket 144 is fixed so as to be sandwiched between the window frame portion 141 and a retaining plate 143 which is also configured in a substantially rectangular frame shape.

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

[0074] The gaskets 144, 146 are made of a rubber material that is less permeable to gas, and by abutting against the abutting surface 71b of the FOUP 7 and the thin wall portion 61a of the door portion 61, it is possible to improve the sealing performance.

[0075] The gaskets 144, 146 can be designed to increase the contact area with the abutment surface 71b of the FOUP 7 and the door portion 61 by appropriately changing the hardness and thickness, thereby improving the sealing performance, so there is no need to provide the clamp unit 5 as shown in the first embodiment to the window frame portion 141. However, if a higher sealing performance is required, such as by increasing the pressure difference between the inside and outside, a configuration in which the clamp unit 5 is provided to improve the sealing performance may be adopted.

[0076] Even in the case of the above configuration, it is possible to obtain the same operational effects as in the first embodiment described above.

[0077] Furthermore, since the elastic material for sealing is formed in a plate shape, the seal structure can be constructed at low cost.

[0078] <Third embodiment> 17 shows a window unit 204 constituting a part of the EFEM 201 and the 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 other than the window unit 204, it is configured in the same way as in the first embodiment. In this embodiment, the same parts as in the first and second embodiments are given the same reference numerals, and the description will be omitted.

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

[0080] The seal member 244 has a substantially rectangular frame shape as shown in Fig. 18(a), and as shown in the cross-sectional shape in Fig. 18(b), a flat plate portion 244a is formed on the outer periphery, and two elastic portions 244b, 244c are formed on the inner periphery, which are branched into an inverted Y shape. The elastic portions 244b, 244c are each shaped to protrude from the inside of the flat plate portion 244a while curving to form a convex shape toward the front and rear. Because of this shape, the elastic portions 244b, 244c have a large deformation margin and can be easily deformed in the front-rear direction.

[0081] Looking at the shape of the above-mentioned sealing member 244 from another perspective, it can also be said that the elastic portion 244b as an elastic material that protrudes forward to seal with the FOUP 7 and the elastic portion 244c as an elastic material that protrudes forward to seal with the door portion 61 are integrally formed via the flat portion 244a.

[0082] As shown in Figure 19, the sealing member 244 is fixed so as to clamp the flat portion 244 between the window frame portion 241 and a retaining plate 243 formed in an approximately rectangular frame shape provided behind it, and the elastic portions 244b, 244c are positioned inside the opening 242 of the window frame portion 241.

[0083] The elastic portions 244b, 244c are capable of performing sealing by elastically contacting the contact surface 71b of the FOUP 71 and the thin portion 61a of the door portion 61. At this time, since the elastic portions 244b, 244c are largely elastically deformable, the contact areas with the contact surface 71b of the FOUP 71 and the thin portion 61a of the door portion 61 can be made large and uniform, thereby providing high sealing performance. Therefore, as in the second embodiment, it is not necessary to provide the clamp unit 5 as shown in the first embodiment in the window frame portion 141, but when higher sealing performance is required, it is acceptable to provide the clamp unit 5 in order to improve the adhesion performance.

[0084] Even in the case of the above configuration, it is possible to obtain the same operational effects as in the first embodiment described above.

[0085] Furthermore, since the elastic portion 244b, which is made of an elastic material provided on the mounting base 34 side for sealing, and the elastic portion 244c, which is made of an elastic material provided on the door portion 61 side, are constructed as a single unit, it is possible to form a sealing structure with a small number of parts, and it is also possible to reduce manufacturing costs.

[0086] The specific configuration of each part is not limited to the above-described embodiment.

[0087] For example, in the above embodiment, the panel 31 as a plate-shaped part is configured by attaching the window unit 4 to the panel main body part 31b, but the two may be configured as one piece without being separated. Specifically, the window frame part 41 constituting the window unit 5 may be configured as one piece without being separated from the panel main body part 31b.

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

[0089] Furthermore, in the above embodiment, the gas supply nozzle 34c serving as the gas supply means is incorporated in the mounting table 34, and the so-called bottom purge method is used to supply gas into the FOUP 7 from below, but the gas supply nozzle 34c may be incorporated in the door portion 61, and the so-called front purge method may be used to supply gas into the FOUP 7 from the front. Even if the load port 3 does not have a gas supply means, it is possible to obtain the same effect as above by using a gas supply device for the inside of the FOUP 3 that is configured separately from the load port 3, such as a so-called purge station, and supplying gas into the FOUP 7 in advance to increase the pressure, and installing the device on the load port 3.

[0090] Furthermore, in the above-described embodiment, nitrogen gas is used as the gas supplied into the EFEM 1 and the FOUP 7, but various gases such as air and ozone can be used depending on the process.

[0091] In addition, in the above-described embodiment, a FOUP7 is used as a wafer storage container, but even when other types of wafer storage containers are used, a similar configuration can be used to obtain effects similar to those described above.

[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 transfer chamber (housing) 3. Loading port 5...Clamp unit (retraction means) 7...FOUP (wafer storage container) 31...Panel (plate-shaped part) 34…Placement table 34c...Gas supply nozzle (gas supply means) 37...Gasket (sealing material) 42...Aperture 44, 46...O-ring (elastic material) 51...Engagement piece 61…Door section 71c…Tsubabe 72…Lid part 73...Gas supply valve 144, 146...Gasket (elastic material) 244b, 244c...Elastic part (elastic material) W: Wafer

Claims

[Claim 1] a plate-shaped portion having an opening for opening the inside of the wafer transfer chamber; A door portion for opening and closing the opening; a mounting table on which the wafer storage container is mounted so that a lid portion that can open and close the internal space of the wafer storage container faces the door portion and on which the wafer storage container can be moved toward and away from the plate-shaped portion; a clamp unit that engages with a flange provided on the wafer storage container to pull the flange toward the plate-shaped portion, The clamp unit includes: an engagement piece that can be engaged with a flange portion provided around the periphery of the lid portion of the wafer storage container; a cylinder capable of advancing and retreating to operate the engaging piece, The load port is characterized in that the engagement piece rotates and engages with the flange portion in accordance with the advancement and retreat of the cylinder.

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