JPH0649529B2 - Transfer method of objects in vacuum chamber - Google Patents

Description

The present invention relates to a method for transferring an object in a vacuum chamber, and more particularly to a method for transferring a semiconductor wafer (hereinafter simply referred to as a wafer) in a vacuum process apparatus.

(Prior Art) In known wafer vacuum process equipment, the wafer transfer (eg, stage-to-stage) is accomplished by a belt, and the wafer is passed from stage to verner or from belt to stage. Delivery is performed by raising and lowering the stage or the belt.

(Problems to be Solved by the Invention) The above-mentioned conventionally known device has a drawback that a stage or belt lifting device is required and the structure of the device is complicated. An object of the present invention is to provide a method for transferring wafers and the like that does not have such drawbacks. Further, the present invention is
An object of the present invention is to provide a method for transferring a wafer or the like in which the generation of dust in the process of transferring the wafer or the like is significantly reduced.

(Means for Solving the Problems) In order to achieve the above-mentioned object, a method of transporting an object in a vacuum chamber of the present invention is a method of transporting an object to a magnetic levitation body that levitates in the vacuum chamber by the action of an electromagnet provided outside the vacuum chamber. An object to be conveyed by the transfer arm is held by moving the magnetic levitation body in the vertical direction, and the object held by the transfer arm is moved by moving the magnetic levitation body in the horizontal direction. In the method of transporting an object in a vacuum chamber in which an object to be transported is placed by moving the magnetic levitation body again at the position, the magnetic levitation body is moved in the vertical direction by controlling the electromagnet. It is what

(Embodiment) An embodiment of the carrying method according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an explanatory view showing an embodiment of the carrying method of the present invention. In the figure, 1 is a manipulator, and 2 is a magnetic levitation body that levitates in a linear passage 3 that communicates with a vacuum chamber in the manipulator 1. The magnetic levitation body 2 levitates and travels in the linear passage 3 by means of guides 4 and 4 provided outside the vacuum chamber and driven by a linear pulse motor. 5 is a wafer cassette provided in the vacuum chamber, 6 is a wafer stage provided in the vacuum chamber, 7 is a wafer supported in a stack in the wafer cassette 5, and 8 is magnetically levitated with one end fixed to the magnetic levitation body 2. The transfer arm extends in the direction of linear movement of the body 2. When a wafer having a diameter of about 76 to 200 mm is transferred from the wafer cassette (or stage) in the vacuum chamber onto the stage, the transfer arm 8 has a thickness of 0.5 to 10 mm.
A long metal or synthetic resin material having a length of 300 to 1800 mm is used.

FIG. 2 is an explanatory view showing a wafer transfer process in the embodiment shown in FIG. In FIG. 2 (a), the carrier 9 including the magnetic levitation body 2 and the carrier arm 8 is a manipulator 1.
3 shows a state of levitating and standing still in the straight passage. In the same figure (b), the magnetic levitation body 2 is moved forward by the guides 4 and 4 provided outside the vacuum chamber and driven by the linear motor, and the tip of the transfer arm 8 is transferred to the transferred wafer 7 in the wafer cassette 5. The state of being inserted in the lower side is shown. FIG. 3C shows a state in which the magnetic levitation body is lifted by the control of a levitation control circuit (not shown) provided outside the vacuum chamber, and the wafer is placed on the transfer arm. The time until the wafer is placed on the transfer arm, that is, the rising time of the transfer arm is lengthened to several seconds to prevent the generation of dust due to the contact between the transfer arm and the wafer. FIG. 4D shows the transfer arm 8
Shows the state in which the wafer supported by the transfer arm is positioned on the wafer stage 6 by advancing. In the figure (e),
The transfer arm 8 is lowered by the control of the levitation control circuit,
The state where the wafer on the transfer arm is placed on the wafer stage is shown. The lowering of the transfer arm 8 is also made to be smooth and to prevent generation of dust. Then, the transfer arm is returned to the state shown in FIG.

When the wafer is transferred from the wafer stage to the wafer cassette, the transfer arm 8 may be operated in reverse.

In the above embodiment, the method of transferring the wafer between the wafer cassette and the wafer stage is shown, but this method can be similarly used for transferring the wafer between the wafer cassette and the wafer stage and between the wafer stage and the wafer stage. Is. This method can also be used to transfer a wafer between three or more wafer stages, between wafer cassettes, or between a wafer stage and a wafer cassette.

(Effect of the Invention) According to the method of the present invention, since the magnetic levitation body and the transfer arm that are moved for wafer transfer move in the vacuum chamber without contact, the generation of dust associated with wafer transfer can be significantly reduced. You can

According to the method of the present invention, the wafer stage raising / lowering mechanism is not required, so that the structure of the apparatus can be simplified.
Further, since the vertical movement of the transfer arm is performed by the magnetic levitation device, an additional device for that purpose is not required.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of a method of transferring a semiconductor wafer or the like according to the present invention, and FIG. 2 is an explanatory view showing a wafer transfer process in the embodiment shown in FIG. 1: Manipulator 2: Magnetic levitation body 3: Linear passage 4: Guide 5: Wafer cassette 6: Wafer stage 7: Wafer 8: Transfer arm

Claims (1)

[Claims] 1. A transfer arm is attached to a magnetic levitation body which floats in the vacuum chamber by the action of an electromagnet provided outside the vacuum chamber, and the transfer arm holds an object to be transferred by moving the magnetic levitation body in a vertical direction. And an object in a vacuum chamber in which the object held by the transfer arm is moved by moving the magnetic levitation body in the horizontal direction and the object to be transferred is placed by moving the magnetic levitation body again at a desired position. The method of transporting an object in a vacuum chamber, wherein the magnetic levitation body is moved in the vertical direction by controlling the electromagnet.