JP2552886B2 - Magnetically levitated crossing conveyor in vacuum - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a magnetic levitation transfer device for transferring a workpiece such as a silicon wafer in a vacuum in a crossing direction so as to perform a process such as sputtering. .

(Prior Art) Conventionally, a work is sequentially conveyed in a vacuum in one direction and in a direction intersecting with the work, and the work is sequentially subjected to treatments such as etching and sputtering. A combination of a belt conveying device, a magnet coupling type linear introducing device, a bellow type linear manipulator device, etc. is known. However, since all of these devices have a sliding portion, dust particles are often generated, which tends to contaminate the work.

(Problems to be solved by the invention) If a magnetic levitation type linear motor is used as a transfer device, non-contact type transfer can be performed and dust generation can be reduced, but the linear motor is used in the transfer route of the work. Since the levitation stator must be arranged along the above, it is difficult to dispose the stator at a position where the workpiece conveying paths intersect, and it is not easy to control the traveling of the mover at the intersection.

It is an object of the present invention to solve the above-mentioned problems when a work is carried in a vacuum by a linear motor on a crossing carrying path.

(Means for Solving the Problems) In the present invention, a work is conveyed in a vacuum along a long linear first work conveying path and a linear second work conveying path intersecting with the first work conveying path. And a first linear motor including a mover that is magnetically levitated by a stator of the linear motor provided along the first workpiece conveyance path and reciprocates.
A second linear motor provided with a linear motor mover that is magnetically levitated by a linear motor stator provided in the second work transfer path and is moved across the mover of the first linear motor. The first linear motor is provided with a work holding table having a space such that the upper surface thereof, the tip of the mover of the second linear motor and the work lifting table can be interposed between the first linear motor and the first linear motor. (2) By providing an elevating and lowering drive device for elevating and lowering the work elevating table to a position above the work holding table and transferring the work between the respective movable elements, beside the intersection of the respective movable elements of the two linear motors, the above-mentioned problems are solved. I tried to solve it.

(Operation) When the mover of the first linear motor is magnetically levitated and the work is placed on the holding table above the mover, the traveling is controlled by the stator to move the mover along the first work transfer path. Transports the workpiece to a position intersecting the second workpiece transport path. When the work arrives at this intersection, the work elevating table is lifted from below by the elevating device, the work on the holding table is received by the work elevating table, and lifted to a position higher than the work holding table.

Next, when the mover of the first linear motor moves and the work lift table is lowered, the work on the work lift table is transferred to the mover of the second linear motor in the middle of the lowering, and the work piece of the second linear motor is moved. Traveling is controlled by the stator, and the mover conveys the work along the second work conveyance path.

The movers of the first linear motor and the second linear motor are reciprocally moved under the control of respective stators, and the lifting device is appropriately moved up and down at the intersection to move the work from the first work transfer path. It is possible to reciprocate through the second work transfer path and further transfer it from the first work transfer path to the original position or to another position. Since the sliding part for the transfer exists only in the lifting device, it is a vacuum. Generation of dust inside is reduced.

(Embodiment) An embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral (1) indicates a vacuum chamber whose interior is evacuated by a vacuum pump, and the vacuum chamber (1) is external A load chamber (3) and an unload chamber (4) for loading and unloading a workpiece (2) such as a silicon wafer, and some processing chambers for performing processing such as sputtering and sputter etching on the workpiece (2) ( 5) (5) is provided. The work (2) is a relatively long linear first work transfer path (6) extending from the load chamber (3) to the unload chamber (4), and intersects the first work transfer path (6) to load the chamber (3) and the unload chamber (4). (4), the workpieces are conveyed along a plurality of linear second workpiece conveying paths (7) and (7) to the respective processing chambers (5) and (5), and in the illustrated example, the workpieces in the load chamber (3) are conveyed. (2) is a processing chamber (5) (5)
It is transported to the unloading room (4) by going through the sequence.

(8) is a first linear motor that conveys the workpiece (2) along the first workpiece conveying path (6), and (9) and (9) are workpieces along the second workpiece conveying paths (7) and (7). The second linear motor to convey, the first linear motor (8) is the second
It is composed of a stator (10) and a mover (11) as shown in the figure, and two stators (10) are provided at intervals along the first work transfer path (6). (11) is constituted by an elongated body having a channel-shaped cross section that covers the upper surface and both sides of each stator (10). Each second linear motor (9) is composed of a stator (12) and a mover (13), and the mover (13) intersects above the mover (11) of the first linear motor (8). As such, it is infested by the stator (12).

Although not shown, the levitation coil and the vertical gap between the stator (10) and the mover (11) are detected in the stator (10) of the first linear motor (8). And a vertical gap sensor that controls the levitation coil so that the upper and lower gaps are uniform, and a drive coil for reciprocating the mover (11) along the stator (10). It is provided. The second linear motor is also levitated and driven by the same principle as the first linear motor.

The work (2) is alternately placed on the movers (11) (13) of the first linear motor (8) and the second linear motor (9) and conveyed, but both movers (11) (13) The specific structure of the crossing portion is as shown in FIG. 2 and FIG.
4) Cantilever fork-shaped work holder (1)
5) is provided, the gap (14) is branched from the side thereof into a fork shape of the mover (13) of the second linear motor (9), the work holding base (15) and the work holding base (15). Tip (16)
Of the fork-like work lift table (17) so as not to collide with the fork of the work piece, the work lift table (17) is located at the side of the intersection of the movers (11) and (13). A lifting / lowering drive device (18) including a vertically moving piston rod introduced from the outside of the vacuum chamber (1) was moved up and down to a position above the work holding table (15). In the embodiment, the three work holders (15a) (15b) (15c) are provided on the mover (11) at equal intervals.

The operation is provided with four second work transfer paths (7) as shown in the first drawing, and four second work transfer paths (7) are provided along each transfer path (7).
To explain the case where the linear motors (9a) (9b) (9c) (9d) and four work lifts (17a) (17b) (17c) (17d) are installed, first, the work is placed in the load chamber (3). When (2) is prepared, the mover (13) of the second linear motor (9a) moves forward to receive the work (2) at its fork-shaped tip (16), and the first work transfer path (6). Retreat to the intersection with. Here, the work elevating table (17a) rises to receive the work (2) on the tip (16) of the mover (13), and is higher than the work holding table (15) of the first linear motor (8). Lift the workpiece (2) to the position. Next, when the mover (11) of the first linear motor (8) moves forward and its work holding table (15a) is positioned below the work lifting table (17a), the work lifting table (17a) descends, On the way, the work (2) is transferred to the work holding table (15a). Subsequently, when the mover (11) of the first linear motor (8) moves backward and its work holder (15a) is positioned above the mover (13) of the next second linear motor (9b), Lift (17b)
Receives the work (2) on the work holding table (15a) and rises, and then the mover (11) of the first linear motor (8).
Moves forward again and the work holding table (15a) is removed from above the work lifting table (17b), the work lifting table (17b) is lowered and the mover (13) of the second linear motor (9b) waiting Pass the work (2) to the tip (16). The mover (13) of the second linear motor (9b) carries the work (2) to the front processing chamber (5), and when it is processed by sputtering or the like, the work elevating table (17b) is again moved. Return to the top. Then, the work lifting platform (17b) is raised to raise the work (2).
Is lifted upward, the mover (11) of the first linear motor (8) moves forward, and when the adjacent work holding table (15b) is located below the lifted work lifting table (17b), the work lifting The table (17b) descends, and the work (2) is transferred to the workpiece holding table (15b) during the descending. After that, the mover (11) of the first linear motor (8) is moved backward, so that the work holding table (15b) is adjacent to the work lifting table (1).
7c), the same work (2) transfer operation as described above is performed, and the work (2) is placed on the next work holding table (15c) and positioned on the last work lifting table (17d). Then, the linear motors (8) (9d) and the work lift (17d) are operated in the reverse order of the load chamber (3), and the processed work (2) is placed in the unload chamber (4).
Is taken out.

(Effects of the Invention) As described above, in the present invention, the first linear motor and the second linear motor in which the movers cross each other along the first work transfer path and the second work transfer path intersecting in vacuum. A motor is provided, and a work holder is provided on the mover of the first linear motor with an interval between the upper end of the mover of the second linear motor and the work lift table that is lifted and lowered by a lift drive device. Since it is provided, the work can be conveyed by magnetic levitation in a vacuum according to the intersecting path, and the structure is relatively simple and the sliding part is only the lifting drive device, so there is little dust generation and it is clean. There are effects such as obtaining a vacuum state.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is a plan view of FIG.
FIG. 3 is an enlarged plan view of an intersection of the movers of the first and second linear motors, and FIG. (1) …… Vacuum chamber (2) …… Work (6) …… First work transfer path (7) …… Second work transfer path (8) …… First linear motor (9) (9a) (9b ) (9c) (9d) …… Second linear motor (10) (12) …… Stator (11) (13) …… Mover (14) …… Spacing (15) (15a) (15b) (15c ) …… Work holder (16) …… Tip (17) (17a) (17b) (17c) (17d) …… Work lift

Claims (1)

(57) [Claims] 1. A method for transporting a work in a vacuum along a long linear first work transport path and a straight second work transport path intersecting the first work transport path, wherein the work is transported along the first work transport path. First linear motor provided with a mover which is magnetically levitated by a stator of a linear motor provided to reciprocate, and magnetically levitated by the stator of the linear motor provided in the second work transfer path, and the first linear motor. A second linear motor provided with a linear motor mover that moves above the mover of the motor, and the mover of the first linear motor has its upper surface and the mover of the second linear motor. Is provided with a work holding table having a space in which the tip of the work piece and the work lifting table can intervene, and the work holding table is provided on the side of the intersection of the movers of the first linear motor and the second linear motor. Upward direction In magnetic levitation cross conveying device in a vacuum, characterized in that the workpiece by lifting is provided an elevating drive device to pass between the mover to.