JPS5833850A - Gate device of valve structure for conveying article between atmosphere and vacuum - Google Patents

Abstract

PURPOSE:To enhance the conveying efficiency of a valve structure by evacuating a space surrounded by upper and lower valve bodies in vacuum when the bodies are hermetically sealed to a seat plate and enabling to introduce atmospheric air to the space, thereby shortening the time required to evacuate the space. CONSTITUTION:A lower article vestivule 27 communicates with a vacuum side and an upper article vestivule 28 communicates with an atmosphere side. A lower assembly 14 is disposed at the lowered position. An article is placed on an article support 19. The assembly 14 is raised, a lower valve body 17 is hermetically engaged with a seat plate 4, and the upper surface of the support 19 is let to slightly upper position from a through hole 5. Atmospheric air is led through an exhaust passage 13 to a space of the hole 5 hermetically enclosed by the plate 4, and the upper and lower valve bodies 8 and 17. The valve body 8 is raised and is upwardly isolated from the plate 4. The article is carried out from the support 19 to the atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a valve structure gate device for conveying articles through atmosphere and vacuum. The gate device of the present invention is particularly suitable for transporting flat articles such as wafers, that is, substrates.

Generally, in order to perform high-efficiency and high-quality vacuum surface treatment, a method is used in which the substrate is slowly and slowly brought into and taken out of the vacuum. In this case, the vacuum chamber is formed into a multi-chamber structure, with the first chamber and the final chamber being formed as chambers for replacing air with vacuum.

This atmosphere-vacuum exchange chamber naturally requires a vacuum gate. For example, when transporting from the atmosphere to a vacuum, the article is carried into the vacuum gate, and after closing the entrance, the inside of the vacuum gate is evacuated. However, a method is adopted in which the connection port between the vacuum chamber and the vacuum gate is then opened and the article is carried into the vacuum chamber from inside the vacuum gate.

In these conventional exchange chambers, 1) two vacuum darts are missing in the @ class, 2) the exchange chamber itself and the gate have a large space, which increases the evacuation time, and S) the chamber requires its own transport system. There are drawbacks such as. In addition, taking these into consideration, the 90,000 type has been proposed, in which the Ge F valve itself has an air-vacuum replacement function, but since this also uses the sliding action of the board's own weight to transport the board, l) The feeding operation subtly affects the conditions of the board, resulting in poor reproducibility, and 2) There is a possibility of chipping or cracking of the board.
.

3) The transfer mechanism of the substrate o*y in the vacuum chamber and the transfer of the substrate to the next mechanism section is often complicated and has drawbacks such as lack of versatility.

Therefore, the present invention provides a device for conveying articles in an atmosphere and vacuum chamber which eliminates such conventional drawbacks.
It is attached to the casing so that it can move up and down within the casing, and has a through hole formed in the center of the seat plate and a downwardly directed peripheral edge. an upper valve body which is attached to the casing by a tubular shaft for vertical movement within the casing and which in the raised position comes into air-tight engagement with the bottom surface of the seat plate around the through hole; a lower valve body which is attached to the tubular shaft so as to be movable up and down within the casing by means of a vertical shaft passing through the tubular shaft, and whose upper surface in the raised position is located slightly above the through hole; The support body has upper and lower article entrances formed in the casing above and below the seat plate, respectively, and further enclosed by the upper and lower valve bodies when the seats are in airtight engagement. It is characterized by the fact that the space in which it is placed can be evacuated to a vacuum and the atmosphere can be introduced.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In the embodiment shown in FIGS. 1 to 3, the device of valve structure II-) has a casing l of square horizontal cross section, inside which all vertical walls -am A relatively thick horizontally extending seat plate is arranged integrally with the rear wall J and both 1111tc.

The seat plate has a circular through hole 5 in its central portion that passes through it vertically.

A horizontal disc-shaped upper valve body t is fixedly attached to the lower end of the upper shaft 7 which passes through the center of the upper pH of the casing 10 so as to be able to rise and fall to 111 m.
An ill-shaped gasket 10 having a diameter similar to that of the through hole S is attached to the lower end m of the peripheral edge, so that when the upper shaft is lowered, the peripheral edge is rotated around the through hole S by the action of the gasket 10. Airtightly engages the upper surface of the seat plate. Upper Wcj of upper ll group? K1m on the upper axis 7! A disk-shaped piston 1/& of a piston-cylinder system 11 is fixed, which is movable in the axial direction of the upper axis, ie vertically, in a cylinder tib fixed to the upper wall 6. According to this configuration, the fluid opening/
The upper shaft and the upper valve body l can be moved up and down by supplying pressure fluid in and out from the outside via the core (a or l).

Exhaust passage 13 that passes through the upper shaft 7 and opens at the lower surface of the upper valve body S
can be connected to a vacuum source (not shown), such as a vacuum pump, and can be connected to atmosphere for purposes described below.

The lower assembly, generally designated by the symbol lda, includes a tubular shaft 14 that vertically and airtightly passes through the center of the lower wall of the casing l in an airtight manner so as to be able to rise and fall; /
1. An end @/AsL fixed to the lower end of the tubular shaft l&, a vertical shaft it passing airtightly through the center of the lower valve body l comb and the end plate/Am in a vertically movable manner and extending inside the tubular shaft 14, and an alignment Kf.
ii--A disk-shaped article support 11 fixed to the upper end of the vertical axis it, its main 11! be a constituent element.

Lower J! I/jK is a disk # fixed to the tubular shaft 16 to which the cylinder θ & of the co-piston-cylinder system Co0 is fixed.
The O piston ob can move vertically in the cylinder 201. Therefore, by allowing pressure fluid to enter and exit from the outside into the space inside the cylinder 2 core a through the fluid opening 2/a or 2/b provided in the cylinder core 011LrC, the lower valve body l? can go up and down.

Further, the cylinder 2a of the two third piston/cylinder systems is fixed to the lower surface of the cylinder Q&, and can be vertically moved within the disk-shaped piston ubtj cylinder koko a identified at the lower end of the vertical *@It.

Therefore, the article support 19 can be moved up and down by introducing and discharging pressure fluid from the outside into the space inside the cylinder 2 core a through the fluid opening loco 3a or 3b provided in the cylinder 22aK. 2 may cooperate so that the article support 1 and the lower valve body 1 move up and down in conjunction with each other.

Two annular seals with a diameter larger than that of the through hole S are attached to the upper surface of the lower valve body 17. Therefore, when the lower valve body 17 rises, the lower valve body 17 is rotated by the through hole S by the action of the packing rod, and is attached to the lower surface of the seat plate. Maintain airtightness. Front article support/
The position of the disc-shaped piston 2b is determined by the stroke length of the vertical axis is so that when l rises, its upper surface passes through the through hole S and comes out slightly above.

The lower assembly further includes a first bellows 25. which surrounds the vertical axis /1 and is soldered to the lower surface of the article support and the upper part of the lower valve body /7. In addition, a second bellows roller is provided which surrounds the tubular shaft 16 and is arranged on the lower surface of the lower valve body 17 and the upper surface of the lower valve body.

A lower article inlet/outlet 7 is formed in the slot wall 2 of the casing 1 just below the seat plate 2, and an upper article inlet/outlet 7 is formed just above the seat 11JKFi seat &da.

Disc-shaped article support 19Fi Relatively deep $3 extending in the front and back direction leaving arch-shaped upper surface portions 19 and 30 on the left and right sides
/ (see also Figure 3), the purpose of which will be made clear later.

The dart with the valve structure as described above can operate in 11 different ways. To explain this example, when the lower article inlet/outlet loaf communicates with the vacuum side and the upper article inlet/outlet port t communicates with the atmosphere side, when articles are not conveyed, the upper valve body l is As shown, it is in the lowered position and sealingly engages the seat f4c. Therefore, the vacuum hook and the atmosphere are separated from each other in the gas phase.

There is an upper valve body t in the place where articles are transported from the vacuum side to the atmosphere side.
The lower assembly (lower valve body 17 and article support/?) is then brought into the lowered position as shown in FIG. The protruding end 3S of the article conveyor A, 7* mounted on the belt conveyor (having a roller 33) is thrust into the groove 31 of the article supporter/9 from the atmosphere side through the lower article entrance/exit 24!, and then the article support A/D is slightly raised, so that a flat article such as a wafer 36 carried from the vacuum side by the article carrier 341K comes to rest on the upper surface portion 30 of the article support 1. At this time, The position of the wafer 36 is as shown in FIG.
Da 4IK its protruding end 3! After the valve f has retreated to the vacuum side, the lower assembly l# is raised, and the lower valve body l# is hermetically engaged with the seat plate da as shown in FIG. The upper surface of the through hole S comes to protrude slightly upward. This raising of the lower assembly/4I can be accomplished with the upper valve body t in airtight engagement with the seat plate.
Atmospheric air is introduced into the space at the through hole S, which is hermetically surrounded by the lower valve body 17, through the exhaust passage 13. After the introduction of the atmosphere is completed, the upper valve body t is raised as shown in FIG. 2 and separated upward from the seat and da. At this time, since the lower valve body 17 is in airtight engagement with the seat 1fjLda, the atmosphere on the vacuum side communicating with the lower article loading/unloading lock is not impaired. After the article is lifted to the uppermost position, an article carrier 3t such as a protruding rod 37 is thrust into the groove 31 of the article support 19 from the atmosphere side through the upper article inlet/outlet g.
Next, the article support 1 is lowered slightly, and the article 36 supported by it is transferred to the article conveyor 33. Next, pull out the article carrier 3g to the atmosphere and move the article 34F.
i can be carried away into the atmosphere.

Next, when repeating the work of Mr. IjJ, the upper valve body j is airtightly engaged with the seat plate with the lower valve body 1 kept in airtight alignment with the seat plate, and then the upper valve body 11 and the lower valve The space surrounded by the body 17 and the seat is evacuated to a vacuum via the exhaust passage 13. If the lower assembly is then lowered to the position shown in FIG. 1, operation back to the position shown in FIG. 1 is accomplished without any loss of vacuum on the vacuum side.

By substantially reversing the procedure described above, it is also possible to convey the article from the atmosphere side to the vacuum side by communicating the upper article inlet/outlet col to the atmosphere side and communicating the lower article inlet/outlet λ7 to the vacuum side. In this case as well, transportation can be achieved without damaging the atmosphere on the vacuum side.

Furthermore, the article J4 can be transported from the vacuum side communicating with the upper article inlet/outlet tK to the atmosphere side communicating with the lower article inlet/outlet tK without damaging the atmosphere on the vacuum side. In that case, the J-th arrow 39 is soldered between the upper valve body t and the upper valve body t, and the J-th arrow 4#i can be omitted.

Since the valve structure game of the present invention is constructed and operated as described above, it does not utilize the weight of the article itself, so there is no need for a complicated conveyance guide mechanism, and the article support l device that moves up and down allows the conveyance of the article. The space that needs to be evacuated for transportation is achieved by the associated article conveyance tools 3 and 3K, so that the space that needs to be evacuated is covered by a seat plate, an upper valve body t that airtightly engages therewith, and a lower valve. Since it is an extremely narrow space surrounded by the body 17, it has the advantage that the time required for evacuation is short and the efficiency of conveyance is high.

[Brief explanation of drawings]

1 and 2 are schematic vertical cross-sectional views of an embodiment of the gate of the invention in two different stages of operation, and FIG. 3 shows an article support contained in the gate of FIGS. 1 and 2. It is a view seen from above. In the drawings, l is the casing, 1IFi seat plate, S is the through hole, tFi upper valve body, 13 is the passage for evacuation, lda is the lower assembly, tb i; is the tubular shaft, /7F
i is the lower valve body, 11 is the vertical axis, /9 Fi is the article support, λ is the lower article inlet/outlet, and col is the upper article inlet/outlet.

Claims (1)

[Claims] An integrated horizontal seat plate inside the casing, seat 1i0
The casing K11l is attached to a through hole formed in the center part and has a downward peripheral edge so that it can be moved up and down within the casing, and in the lowered position, the peripheral edge is airtightly engaged with the seat plate 1iiK by the rotation of the through hole. The upper valve body is attached to the casing by a tubular shaft so as to be able to move up and down within the casing, and the lower valve body, which is tubular in shape, is brought into airtight engagement with the lower surface of the seat plate by means of a through hole in the raised position. Penetrate through the shaft! The article support is attached to the tubular shaft so as to be able to move up and down within the casing by means of the 11I shaft, and whose upper surface is located slightly above the through hole in the raised position, and above and below the seat plate. The casing has an upper and a lower article inlet/outlet, respectively, and when the upper valve element and the lower valve element are in airtight engagement with the seat plate, the nine valves that come into contact with these can be evacuated to a vacuum, and can be vented to the atmosphere. A gate device having a valve structure for conveying articles between atmosphere and vacuum, characterized in that a gate device can be introduced.