JPS62264128A - Wafer conveying device - Google Patents

Abstract

PURPOSE:To provide a miniature wafer conveying device which performs precise shift motion, by driving a wafer holding section with the use of a voice coil motor which is controlled by a control device to carry out shift motions so that no detrimental effects are given to vacuum, purification and the like. CONSTITUTION:A disc-like permanent magnet 1 is secured thereto with a center piece 2 and is disposed in the center section within a yoke 3 to form a magnetic circuit. An annular coil 5 is projected from one surface of a disc-like bobbin 4 and two semicircular electrostatic chucking electrodes 7a, 7b are secured to the other surface through the intermediary of an insulating sheet 6 to form a wafer holding section. Further, the annular coil 5 in the bobbin 4 is disposed in an annular gaps defined between the permanent magnet 1 and the center piece and the yoke 3, and is supported by a leaf spring 8 to constitute a shift motion device 9 composed of a voice coil motor and the wafer holding section. This shift motion device 9 is rotatably arranged at the front end of a conveying device 10, and is disposed in a vacuum chamber in an ultrahigh vacuum CVD device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a wafer transport device that transports wafers.

(Prior Art) Semiconductor devices such as VLSIs are generally manufactured by subjecting wafers to various treatments.

Most of these processes are performed at A1 temperature and under high vacuum, so for example, processing equipment that performs processing under high vacuum has a wafer transport system that transports and places the wafer at a predetermined placement location in a vacuum container. Many are equipped with equipment.

Conventional wafer transport devices are driven using a transport device that transports a wafer held in a wafer holder to a predetermined placement location, and a mechanical handling arm using, for example, an air cylinder or a screw. and a placement operation device for placing the wafer held by the wafer at the placement location.

(A problem that the invention is trying to solve) However, in the conventional wafer transfer device that uses a handling arm as a loading operation device, the mechanism becomes complicated and the device becomes large. As a result, there is a problem in that more dust is generated. In addition, with a wafer transfer device that uses an air cylinder as the loading operation device, it is possible to climb onto a relatively small helicopter, but the problem is that the controllability of speed and position control is poor, and there is a possibility of damaging the wafer. However, there is a problem with air leaking inside the vacuum container and negatively affecting the vacuum level.

The present invention has been made in response to such conventional problems,
A wafer transfer V that is compact and can perform accurate placement operations without adversely affecting the degree of vacuum or cleanliness.
The aim is to provide tM.

[Structure of the Invention] (Means for Solving the Problems) That is, the wafer transfer device of the present invention includes a transfer device, a voice coil motor controlled by a control device, and a wafer holding device driven by the voice coil motor. It is equipped with a mounting operation device for controlling the parts.

(Function) In the wafer transfer device of the present invention, the wafer holder is driven by a voice coil motor controlled by a control device to perform a placing operation.

(Example) The details of the present invention will be described below with reference to an example shown in the drawings.

FIGS. 1 and 2 show the main parts of an evaporator conveying device according to an embodiment of the present invention. For example, a disk-shaped permanent magnet 1 made of a rare earth cobalt magnet and whose surface is plated with nitrile is A center piece 2 made of a metal with high magnetic permeability, such as 5S41, etc. is fixed, and is housed and fixed in the center of a yoke 3 made of a similar metal formed on the container to form a magnetic circuit.

Further, a circular coil 5 made of a polyimide-coated electric wire is protruded from one side of the disk-shaped bobbin 4 made of a paramagnetic material such as aluminum, and a ring-shaped coil 5 made of an electric wire coated with polyimide is provided on the opposite side. Two semicircular electrostatic chuck electrodes 7a and 7b are fixed via an insulating sheet 6,
A holding portion is formed.

The annular coil 5 of this bobbin 4 is connected to the permanent magnet 1.
The voice coil motor and the A loading operation device 9 including a wafer holding section is configured.

Note that the loading operation device 9 is disposed at the tip of the conveyance device 10.
The coil 5 is connected to a control device (not shown).

In such a mounting operation device 9, when a current I is applied to the coil 5, the magnetic flux density due to the permanent magnet 1 is B, the angle between one flux and the coil 5 is θ, and the length of the coil 5 is β. A force F represented by F=IBJSinθ is applied to the coil 5. Further, the bobbin 4 is elastically held by a leaf spring 8.
The moving distance of the bobbin 4 is determined by the balance between the spring coefficient and the force F.

Therefore, a control device (not shown) controls the amount of current I flowing through the coil 5 and the amount of change in this current I per unit time, thereby controlling the moving distance and moving speed of the bobbin 4.

The wafer transfer device is configured such that the loading operation device 9 is rotatably disposed at the tip of the transfer device 10, as shown in FIG. This wafer transfer device is arranged, for example, in a sub-vacuum chamber 11 of an ultra-high vacuum CVD apparatus having a sub-vacuum chamber 11 and a main vacuum chamber 12.

In ultra-high vacuum CVDE equipment, the sub-vacuum chamber 11 and the main vacuum chamber 12
and are communicated by an opening 14 having an isolation door 13. When placing the wafer on the heating table 15 of the main vacuum chamber 12, first close the door 13 of the partition 1i111, set only the sub-vacuum chamber 11 to normal pressure, and place the wafer through the opening/closing door 16 using the electrostatic chuck. The liquid is adsorbed onto the electrodes 7a and 7b.

Thereafter, the inside of the sub-vacuum chamber 11 is evacuated, the isolation door 13 is opened, the wafer is transported to above the heating table 15 by the transport device 10, and the wafer is brought into contact with the heating table 15 by the mounting operation device 9. Then, the wafer is placed on the heating table 15 by turning off the electrostatic jack of the wafer holding section.

As described above, since the wafer transfer apparatus of this embodiment is equipped with the mounting operation device @9 that drives the wafer holding section by a voice coil motor, the degree of vacuum is adversely affected due to leakage of driving air.

It's not enough. Furthermore, since it is small and has few mechanical drive parts, less dust is generated and a clean atmosphere can be maintained. Furthermore, by controlling the current applied to the coil 5 and the change in current per unit time, the moving speed and position of the wafer holder during the loading operation can be accurately controlled. Since the mounting operation can be performed, the wafer will not be damaged.

[Effects of the Invention] As described above, the wafer transfer device of the present invention uses a voice coil motor to drive the wafer holder and includes a loading and unloading device that performs the U and placing operations, so the vacuum level, cleanliness, etc. It is possible to perform a compact and accurate placement operation without adversely affecting the device.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing the main parts of a wafer transfer device according to an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG. FIG. 2 is a vertical cross-sectional view of an ultra-high vacuum CVD apparatus, not showing the structure. 1... Permanent magnet, 2... Center piece, End... Yoke, 4... Bobbin, 5...
......Coil, 7a17b... Electrostatic chuck electrode, 8... Leaf spring, 9...M,
positioning device, 10... transportation device;

Claims (1)

[Claims] (1) A wafer transfer device comprising a transfer device, a voice coil motor controlled by a control device, and a placement operation device having a wafer holder driven by the voice coil motor.