The present invention relates to a gate valve and a substrate processing system using same.
In a manufacturing process of a flat panel display (FPD) represented by a liquid crystal display (LCD) or a solar cell, a predetermined treatment such as etching, film formation or the like is performed on a large-size glass substrate. As for a substrate processing system for performing such treatment, there is known a multi chamber type substrate processing system having a plurality of processing chambers (e.g., Japanese Patent Application Publication No. H5-196150 (JP5-196150A) and Japanese Patent Application Publication No. 2011-54928 (JP2011-54928A)).
Such multi chamber type substrate processing system includes a common transfer chamber where a transfer device for transferring a substrate (an object to be processed) is provided. Further, a processing chamber and a load-lock chamber where an unprocessed substrate is exchanged with a processed substrate from the common transfer chamber under the atmospheric environment are provided around the common transfer chamber. The common transfer chamber, the processing chamber and the load-lock chamber are vacuum devices, and each of the insides thereof is exhausted to a predetermined depressurized state by operating a gas exhaust unit.
The vacuum device has an airtight vessel main body, and an opening for loading and unloading an object to be processed is formed at the vessel main body. The opening is opened and closed by using a gate valve. When the opening is closed by the gate valve, the vessel main body is airtightly sealed. Accordingly, a pressure in the vessel main body can be decreased to a predetermined processing pressure or switched between an atmospheric state and a depressurized state.
As for an example of the gate valve, there are known one using a link mechanism described in JP5-196150A and one using a cam mechanism described in JP2011-54928A.
As the trend toward scaling up of an object to be processed or batch type processing for simultaneously processing a plurality of objects to be processed advances, a size of an opening that is formed at the vessel main body to load and unload an object to be processed tends to be increased. Further, in the batch type processing, it is considered to increase the number of objects to be processed that can be processed simultaneously in order to suppress decrease of a throughput or to maintain/improve a throughput.
However, if the number of objects to be processed simultaneously is increased, the size of the opening is increased in a height direction, and an elevation distance of a valve body is also increased, thereby making it difficult to install a substrate processing system in a manufacturing factory.
In view of the above, the present invention provides a gate valve that can reduce an elevation distance of a valve body even when the number of objects to be processed simultaneously is increased, and a substrate processing system using the same.
In accordance with one aspect of the present invention, there is provided a gate valve including: a plurality of openings through which objects to be processed are loaded and unloaded; a valve body to be pressed toward the openings; a pressed portion provided to the valve body; a main slider slidable in parallel with a surface where the openings are formed; and a cam, provided to the main slider and having a protrusion and an inclined portion inclined from the protrusion in a sloped shape, for pressing the pressed portion of the valve body in a state where the valve body faces the openings, wherein the valve body has one or more slit-shaped openings serving as opening portions for opening the openings, and portions adjacent to the slit-shaped openings serving as blocking portions for blocking the openings.
In accordance with another aspect of the present invention, there is provided a substrate processing system including: a processing chamber having an opening through which an object to be processed is loaded and unloaded, the processing chamber serving to accommodate the object in a vacuum state and process the object; a load-lock chamber having an opening through which the object is loaded and unloaded, the load-lock chamber serving to accommodate the object in an atmospheric state as well as in a vacuum state and exchange an unprocessed object with a processed object; and a transfer chamber having an opening through which the object is loaded and unloaded, the transfer chamber serving to accommodate the object in a vacuum state and transfer the object between the load-lock chamber and the processing chamber, wherein the gate valve described in claim 1 is used as a gate valve for opening and closing the opening of at least one of the processing chamber, the load-lock chamber and the transfer chamber, through which the object is loaded and unloaded.
In accordance with the present invention, it is possible to provide a gate valve that can reduce an elevation distance of a valve body even when the number of objects to be processed simultaneously is increased, and a substrate processing system using the same.
The objects and features of the present invention will become apparent from the following description of embodiments, given in conjunction with the accompanying drawings, in which:
Embodiments of the present invention will be described with reference to the accompanying drawings which form a part hereof. Throughout the drawings, like reference numerals refer to like parts.
In the present embodiment, a substrate processing apparatus for performing a predetermined treatment, e.g., etching, film formation or the like, on an object to be processed, e.g., a glass substrate used for fabrication of a FPD or a solar cell, will be described.
As shown in
In the present embodiment, the processing chambers 10a and 10b, the load-lock chamber 20, and the common transfer chamber 30 are vacuum devices, and have airtight vessel main bodies 50a, 50b, 50c and 50d, respectively, each being capable of accommodating substrates G under a predetermined depressurized state. The vessel main bodies 50a to 50d are provided with openings 51a to 51d for loading and unloading substrates G. An opening 51e for loading and unloading a substrate G between the load-lock chamber 20 and the outside of the substrate processing system 1 is further provided at the vessel main body 50c of the load-lock chamber 20. The opening 51e is used for loading an unprocessed substrate G into the substrate processing system 1 and unloading a processed substrate G from the substrate processing system 1.
The common transfer chamber 30 is connected to the processing chambers 10a and 10b and the load-lock chamber 20 via gate valve chambers 60 accommodating therein gate valves. In the present embodiment, three gate valve chambers 60 are provided. Each of the gate valve chambers 60 forms a vacuum device having an inside that can be maintained in a predetermined depressurized state as in the vessel main bodies 50a to 50d.
Provided at the gate valve chambers 60 are openings 61 communicating with the openings 51a to 51c formed at the vessel main bodies 50a to 50c of the processing chambers 10a and 10b and the load-lock chamber 20 and openings 62 communicating with the openings 51d formed at the vessel main body 50d of the common transfer chamber 30. Substrates G are loaded and unloaded among the common transfer chamber 30, the processing chambers 10a and 10b and the load-lock chamber 20 via the openings 61 and 62.
The gate valve chamber 60 accommodates therein a valve body 63 of a gate valve. The valve body 63 of the gate valve is mainly formed by a unit for airtightly opening and closing an opening formed at one side of the gate valve chamber 60. In the present embodiment, the valve bodies 63 open and close the respective openings 61 (between the openings 61 and 62) for the processing chambers 10a and 10b and the load-lock chamber 20. The valve bodies 63 are pressed to the respective openings 61 and brought into airtight contact with the peripheries of the openings 61. Accordingly, the openings 51a to 51c are blocked, and the vessel main bodies 50a to 50c of the processing chambers 10a and 10b and the load-lock chamber 20 are airtightly sealed. The atmospheric side opening 51e of the load-lock chamber 20 is opened and closed by a valve 63a for allowing or blocking communication with an external environment in an atmospheric state.
As shown in
As shown in
If one of the openings 61 is opened and closed by the elevation operation of the valve body 63 on the assumption that the number of the openings 61 is two, the number of the slit-shaped opening 65 is one.
In the gate valve in accordance with the embodiment of the present invention, a plurality of openings 61 (61a to 61d) for loading and unloading substrates G is provided at the sidewalls of the gate valve chamber 60 or at the opening plates 64, and one or more slit-shaped openings 65 (65a to 65c) are provided at the valve body 63 for opening and closing the openings 61a to 61d in accordance with the number of the openings 61. Further, four portions adjacent to the slit-shaped openings 65a to 65c in the height direction serve as blocking portions 66a to 66d for blocking the openings 61a to 61d, and the slit-shaped openings 65a to 65c serve as opening portions for opening the openings 61b to 61d among the openings 61a to 61d.
With the above configuration, even when the number of substrates G processed simultaneously is increased as shown in
In the comparative examples as well as the above-described embodiment, four substrate processing units 100a to 100d are laminated in the height direction. Further, a single opening 161 is formed at an opening plate 164 and opened and closed by a single valve body 163.
As shown in
When the number of the laminated processing units 100 is increased as in the case of providing processing units 100a to 100f as shown in
In accordance with the present embodiment, the elevation distance S of the valve body 63 is not changed even when the number of the processing units 100 is increased as in the case of providing the processing units 100a to 100f as shown in
Besides, in accordance with the present embodiment, since the elevation distance S is short, the period of time required to open and close the valve body 63 can be reduced, and a throughput can be improved.
Further, since the elevation distance S is short, the opening/closing speed of the valve body 63 can be reduced. If the opening/closing speed is reduced, it is unnecessary to provide a stopper below a main slider 70 which is required for a high-speed opening/closing operation. Furthermore, generation of dust particles can be suppressed.
Hereinafter, an operation example of a gate valve in accordance with the embodiment of the present invention will be described.
As shown in
The main slider 70 is provided with a pressing unit 71 that presses the valve body 63 toward the openings 61a to 61d in a state where the valve body 63 directly faces the openings 61a to 61d. The valve body 63 is provided with a pressed portion 67 pressed with the pressing unit 71. The pressing unit 71 is configured as, e.g., a cam having a protrusion 72 and an inclined portion 73 inclined in a slope shape from the protrusion 72. The pressed portion 67 is configured as, e.g., a protrusion having a roller 68 that comes into contact with the cam (the pressing unit 71). The roller 68 rolls on the surfaces of the protrusion 72 and the inclined portion 73 by the sliding of the pressing unit 71, i.e., the vertical movement of the pressing unit 71 in the present embodiment.
(In the Case of Blocking the Openings 61a to 61d)
In the case of blocking the openings 61a to 61d by using the valve body 63, the positions of the blocking portions 66a to 66d are misaligned so as to directly face the openings 61a to 61d (
In the present embodiment, the main slider 70 has a hook portion 74 to which the sub-slider 80 is hooked. Further, in the present embodiment, a valve body stopper 90 for stopping the sliding of the valve body 63 is provided on the bottom surface of the gate valve chamber 60.
Until the sliding of the valve body 63 is stopped by the valve body stopper 90, the valve body 63 held by the sub-slider 80 is lowered by the sliding of the main slider 70, i.e., the downward movement of the main slider 70 in the present embodiment. When the downward movement of the valve body 63 is stopped by the valve body stopper 90, the sub-slider 80 is separated from the hook portion 74. The downward movement of the main slider 70 is continued even after the sub-slider 80 is separated from the hook portion 74. Then, the roller 68 of the pressed portion 67 is brought into contact with the inclined portion 73 of the pressing unit 71 and starts to roll along the inclined portion 73 toward the vertex of the protrusion 72.
Provided between the valve body stopper 90 and the valve body 63 is a roller 69 for reciprocally moving the valve body 63 in a direction that allows the valve body 63 to directly face a surface where the openings 61a to 61d are formed. In the present embodiment, the roller 69 is provided at the lower portion of the valve body 63. The roller 69 rolls on the horizontal top surface of the valve body stopper 90 when the roller 68 starts to roll toward the vertex of the protrusion, thereby moving the valve body 63 toward the openings 61a to 61d. As a consequence, the valve body 63 is pressed toward the surface where the openings 61a to 61d are formed by the cam of the pressing unit 71 and, then, the openings 61a to 61d are blocked by the blocking portions 66a to 66d (
(In the Case of Opening the Openings 61a to 61d)
In the case of opening the openings 61a to 61d by using the valve body 63, the pressing achieved with the cam of the pressing unit 71 is released and the positions of the slit-shaped openings 65a to 65c of the valve body 63 are moved so as to directly face the openings 61b to 61d. In the present embodiment, the number of the slit-shaped openings 65a to 65c is smaller than that of the openings 61a to 61d by one. Thus, the valve body 63 is moved from the position directly facing the opening 61a.
In the present embodiment, the sub-slider 80 has a return unit 81. The return unit 81 returns the valve body 63 from position of the surface where the openings 61a to 61d are formed to the original position when the pressing achieved with the cam of the pressing unit 71 is released. The return unit 81 is configured as a unit having, e.g., a spring 82 and a spring pressing portion 84, for reciprocally moving the valve body 63 in a direction that allows the valve body 63 to directly face the surface where the openings 61a to 61d are formed. The spring 82 is contracted when the valve body 63 is pressed toward the openings 61a to 61d. When the pressing is released, the spring 82 is extended and, hence, the valve body 63 is returned so as to be away from the openings 61a to 61d. The spring 82 may be substituted with any component as long as it is extensible/contractible likewise.
When the main slider 70 slides, i.e., moves upward in the present embodiment, the roller 68 starts to roll along the inclined portion 73 from the vertex of the protrusion 72 contrary to the case of blocking the openings. At the same time, the springs 82 is extended, and the valve body 63 returns to the original position from the openings 61a to 61d. At this time, the roller 69 rolls on the horizontal top surface of the valve body stopper 90 and retreats the valve body 63 from the openings 61a to 61d. Then, when the sub-slider 80 is hooked to the hook portion 74 of the main slider 70, the main slider 70 raises the sub-slider 80 and the valve body 63 in a direction parallel to the openings 61a to 61d. The main slider 70 raises the sub-slider 80 and the valve body 63 until the slit-shaped openings 65a to 65c directly face the openings 61b to 61d and the valve body 63 is misaligned with the opening 61a. Accordingly, the openings 61a to 61d are opened by the slit-shaped openings 65a to 65c and the valve body 63 (
Hereinafter, specific examples of the main slider 70 and the sub-slider 80 will be described.
As shown in
In the present embodiment, one or more sub-sliders 80 are provided between both outer sides of the cutoff portion 75 of the main slider 70 through which the substrate G passes and both side portions of the valve body 63. The gap between the sub-sliders 80 provided at both side portions is set to be greater than the horizontal size of the substrates G passing through the slit-shaped openings 65a to 65c. Hence, the loading and unloading of the substrates G is not disturbed by the sub-sliders 80. In order to ensure stable operation of the valve body, it is preferable to provide the same number of the sub-sliders 80 at both sides symmetrically. The number of the sub-sliders 80 may be two or more depending on the size of the valve body. When stable operation of the valve body can be ensured, it is not essential to provide the same number of the sub-sliders 80 at symmetrical locations.
Ribs 91 are provided at a surface of the blocking portions 66a to 66d which is opposite to the surface where the openings 61a to 61d are formed. When the main slider 70 is provided with the cutoff portion 75 through which the substrate G passes as in the present embodiment, the blocking portions 66a to 66d are exposed through the cutoff portion 75. In other words, the blocking portions 66a to 66d cannot be pressed by the pressing unit 71. Therefore, when the blocking portions 66a to 66d are subjected to a back pressure generated by the processing chambers 10a and 10b or the load-lock chamber 20 through the openings 61a to 61d, the blocking portions 66a to 66d are bent and this may results in deterioration of airtightness.
In order to suppress the deterioration of airtightness, the ribs 91 may be provided at the blocking portions 66a to 66d as in the present embodiment. The main slider 70 is provided at the sides of the blocking portions 66a to 66d, and the pressed portions 67 of the valve body 63 are pressed by the pressing units 71. Thus, the bending of the blocking portions 66a to 66d is prevented by the ribs 91, thereby suppressing the deterioration of airtightness.
The rib 91 may be a rectangular rod-shaped member of which cross section has a major axis and a minor axis, or may be a truss-shaped member having a triangular cross section.
In case of the rod-shaped member, it is preferable to have a surface 91a of a minor axis side to be fixed to the blocking portion 66 of the valve body 63 as shown in
The truss-shaped member may be configured by joining an end of a plate 91b with that of a plate 91c and fixing the other open ends thereof to the blocking portion 66 as shown in
As for a unit for sliding the main slider 70, there may be suggested a unit for moving the main slider 70 in a linear motion. An example of the linear moving unit includes an LM (linear motion) guide. In the present embodiment, an LM guide 92 is used as a unit for sliding the main slider 70.
As shown in
In addition, a guide rail 93b is provided at a surface of the sub-slider 80 which corresponds to the main slider 70, and a guide block 94b is provided at a surface of the main slider 70 which corresponds to the sub-slider 80. The guide block 94b is fitted to the guide rail 93b so as to be slidable. Hence, the main slider 70 holds the guide rail 93b of the sub-slider 80. The sub-slider 90 slides, i.e., vertically moves in the present embodiment, along the guide block 94b of the main slider 70 (see
A driving unit 95 for sliding the main slider 70 is provided above the main slider 70. In the present embodiment, two driving units 95 are positioned above both side portions of the main slider 70. The driving unit 95 may be, e.g., an air cylinder, a hydraulic cylinder or the like.
As shown in
In accordance with the above embodiment, it is possible to obtain a gate valve that can reduce an elevation distance of a valve body even when the number of objects to be processed simultaneously is increased, and a substrate processing system using the gate valve.
The present invention is not limited to the above-described embodiment and can be variously modified. Further, the embodiment of the present invention is not limited to the above-described embodiment.
For example, four or six openings 61 are illustrated in the above-described embodiment. However, the number of the openings 61 is not limited thereto, and may be greater than or equal to two.
In the above embodiment, the gate valve chamber 60 has been described as an example of an accommodating body for accommodating a gate valve. However, the accommodating body may also be a valve box for accommodating a gate valve.
In the above embodiment, the glass substrate used for fabrication of an FPD or a solar cell has been described as an example of an object to be processed. However, the object to be processed is not limited to the glass substrate, and may also be another substrate such as a semiconductor wafer or the like.
While the invention has been shown and described with respect to the embodiments, it will be understood by those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.
Number | Date | Country | Kind |
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2011-143129 | Jun 2011 | JP | national |