JP3085969B2 - Plate transfer device - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention relates to a plate-shaped object conveying device.

(Prior Art) Conventionally, in a semiconductor manufacturing process or the like, various types of plate-like body transfer devices have been used as a device for transferring a plate-like body such as a semiconductor wafer.

For example, Japanese Patent Application Laid-Open No. 64-35746 discloses a plate-like body transfer device in which five semiconductor wafer arms are arranged so that the semiconductor wafers are substantially parallel to each other at equal intervals.
A plate-shaped body transfer device is disclosed in which these arms can be moved in parallel by a ball screw provided with portions with different leads on one axis to change the interval between semiconductor wafers.

Such a plate-like body transfer device has a feature that transfer can be performed while changing a pitch (interval) of semiconductor wafers. For example, a semiconductor wafer between a wafer cassette and a wafer boat for a heat treatment apparatus is used. Used for wafer transfer and the like.

(Problems to be Solved by the Invention) However, in the above-described conventional plate-shaped body transport device,
Since the ball screw is used, the screw shaft and the nut are both metal.The height of the device is high, and the ball screw must be turned many times to convert the pitch with high positional accuracy. The area of the sliding part between the metal part of the nut and the nut is large, and a large amount of dust such as metallic dust or lubricating oil mist is generated. There was a problem that there is. In particular, in recent years, with the increase in the degree of integration of semiconductor devices, the need to suppress the generation of dust has increased, and the problem of the generation of dust has become a serious problem.

The present invention has been made in view of such a conventional situation, and provides a plate-like body transfer device capable of reducing the size of the device and reducing the amount of generated metallic dust and oily dust as compared with the related art. It is something to offer.

[Structure of the Invention] (Means for Solving the Problems) That is, the present invention provides a plate-like body transfer device in which a plurality of arms for supporting a plate-like body are arranged so that the plate-like bodies are substantially parallel to each other at regular intervals. In the plate-like body transport device configured to be able to change the interval between the plate-like bodies by moving the arm in parallel, the first arm provided at the center among the plurality of arms is fixed. The second arms provided on both sides of the first arm are opposed to each other by a rack provided on the second arm and a first pinion provided to mesh with the rack. The third arms respectively provided outside the second arm are provided with a rack disposed on the third arm and the third arm provided so as to mesh with the rack. Double the number of teeth of the first pinion It is driven to translate in opposite directions by a second pinion, characterized in that it is configured to change the spacing of the plate-like body.

(Effect) In the plate-like body transporting device of the present invention, the arm supporting the plate-like body has a different diameter from a rack provided on the arm and connected to a drive shaft provided to mesh with the rack. Each of the plurality of pinions is moved in parallel by a predetermined distance to change the interval between the plate-like members.

Therefore, for example, when the arm is driven using the rack and the pinion as compared with the case where the arm is driven using a ball screw, the area of the sliding portion of the drive unit is small,
Generation of dust can be suppressed. Further, the height of the device can be reduced.

(Embodiment) Hereinafter, an embodiment in which the present invention is applied to a wafer transfer apparatus that transfers a semiconductor wafer between a wafer carrier and a wafer boat for a vertical heat treatment apparatus will be described with reference to the drawings.

As shown in FIGS. 1 and 2, a plurality of (five in this embodiment) thin arms 2a to 2a to support a semiconductor wafer 1 which is a plate-like body are provided in a wafer transfer device.
2e is provided. The arms 2a to 2e are arranged so as to be stacked so as to be substantially parallel to each other. The semiconductor wafer 1 supported by these arms 2a to 2e is coaxially substantially parallel and at equal intervals (equal pitch). ).

Further, among these arms 2a to 2e, an arm provided at the center (hereinafter, referred to as a central arm) 2a is fixed, and an arm provided at the outside of the central arm 2a (hereinafter, referred to as a central arm).
The intermediate arms 2b and 2c and the outermost arms (hereinafter referred to as outer arms) 2d and 2e move in parallel in the vertical direction in FIG. Is configured.

The movement of the intermediate arms 2b and 2c and the outer arms 2d and 2e is performed while keeping the distance between the semiconductor wafers 1 equal.
In order to change this interval, the outer arm 2d, 2e is configured to have a moving distance of 2D with respect to the moving distance D of the intermediate arms 2b, 2c. Such a movement is performed by the following mechanism. Has been realized.

That is, two linear sliders 3 each containing a plurality of ball bearings are provided at the ends of the outer arms 2d and 2e. On the other hand, the arms 2a to 2e
In the arm support portion 4 for supporting the semiconductor device, four round bars 5 are erected substantially vertically. Of these round bars 5, two round bars 5 on the semiconductor wafer 1 side (in the figure, The outer arms 2d and 2e are supported by the left side (left side), and the intermediate arms 2b and 2c are supported by the other two round bars 5 (right side in the figure) so as to be vertically movable. The center arm 2a is fixed at a substantially intermediate height position of the arm support portion 4 by a support member (not shown).

The dust generated when the linear slider 3 slides on the round bar 5 is provided with a seal member (not shown) on the linear slider 3 so that the dust is not scattered around.

As shown in FIG. 2, a rotary shaft 10 connected to a motor 9 via pulleys 6 and 7 and a belt 8 is provided substantially at the center of the arm support 4. This rotation axis
The pinion 10 is provided with a pinion 11 made of, for example, a hard resin Delrin (trade name) for the outer arm having a different diameter and a pinion 12 for the intermediate arm. It is set to twice the number of teeth.

On the other hand, the intermediate arms 2b and 2c are provided with racks 13b and 13c, respectively, so as to mesh with a pinion 12 made of, for example, a hard resin Delrin (trade name) for the intermediate arm. That is, the racks 13b and 13c are provided so as to face each other with the intermediate arm pinion 12 therebetween. When the intermediate arm pinion 12 rotates, the racks 13b and 13c cause the intermediate arms 2b and 2c to face in opposite directions. Are moved in parallel by the same distance.

Similarly, the outer arms 2d and 2e are provided with racks 14d and 14e respectively so as to mesh with the outer arm pinion 11, and when the outer arm pinion 11 rotates, the racks 14d and 14e The arms 2d and 2e are configured to translate in the opposite directions by the same distance. The moving distance of the outer arms 2d and 2e is always twice the moving distance of the intermediate arms 2b and 2c. The intermediate arms 2b and 2c and the outer arms 2d and 2e
The shape is such that b, 13c and racks 14d, 14e are misplaced so as to penetrate these arms.

According to such a mechanism, the pitch of the semiconductor wafer 1 can be arbitrarily changed by slightly rotating the motor 9. If the position of any one of the intermediate arms 2b and 2c and the outer arms 2d and 2e is detected by, for example, an optical sensor and the rotation of the motor 9 is controlled,
The intermediate arms 2b and 2c and the outer arms 2d and 2e can be reliably stopped at predetermined positions.

As shown in FIG. 3, the mechanism having the above-described structure includes a horizontal drive mechanism 20 for linearly moving back and forth, an elevating mechanism 21 for moving up and down, and a horizontal rotating mechanism for horizontally rotating.
Provided on 22. Also, the arms 2a to 2e of the mechanism described above
A wafer transfer device is configured by disposing a single-wafer transfer arm 23 that can be moved back and forth independently of these arms 2a to 2e.

A wafer carrier 30 configured to accommodate a plurality of, for example, 25 semiconductor wafers 1 at a predetermined pitch, for example, 3/16 inch, and a wafer carrier 30 at a predetermined pitch, for example, 9/16 inch, for example, 150
The transfer of the semiconductor wafer 1 is performed between the semiconductor wafer 1 and a heat treatment wafer boat 31 configured to accommodate the semiconductor wafers 1.

That is, first, the motor 9 is rotated to set the interval between the arms 2a to 2e to the wafer pitch of the wafer carrier 30 (3/16 inch).
In this state, the arms 2a to 2e are inserted into the lower part of the semiconductor wafer 1 in the wafer carrier 30 by the horizontal drive mechanism 20, the lifting mechanism 21, and the horizontal rotation mechanism 22.

Thereafter, the arms 2a to 2e are lifted by the elevating mechanism 21, whereby one semiconductor wafer 1 in the wafer carrier 30 is placed on each of the arms 2a to 2e (total of 5 wafers), and then the arms 2a to 2e are mounted. The wafer is pulled out of the wafer carrier 30 and transferred to the front of the heat treatment wafer boat 31.

Then, the motor 9 is rotated to set the interval between the arms 2a to 2e to the wafer pitch of the heat treatment wafer boat 31 (9/16 inch).
Then, the arms 2a to 2e are inserted into predetermined positions of the wafer boat 31 for heat treatment, and the arms 2a to 2e are lowered by the elevating mechanism 21, thereby transferring five semiconductor wafers 1 at a time.

By repeating the same operation, a predetermined number of semiconductor wafers 1
Is transferred from the wafer carrier 30 to the wafer boat 31 for heat treatment after the pitch conversion. In the heat treatment step, dermy wafers may be arranged above and below the heat treatment wafer boat 31 or monitor wafers may be arranged between a predetermined number of semiconductor wafers 1. The transfer is performed one by one using the leaf transfer arm 23. When the heat treatment is completed, the processed semiconductor wafer 1 is transferred from the heat treatment wafer boat 31 to the wafer carrier 30 in a procedure reverse to the above procedure.

As described above, according to the present embodiment, the pitch of the semiconductor wafer 1 is changed by the racks 14d and 14e and the pinion 11 for the outer arm, and the racks 13b and 13c and the pinion 12 for the intermediate arm. For example, compared to the case where a ball screw is used, a motor 9 required for pitch conversion is used.
Can be reduced, and the amount of generated dust can be reduced. Further, the size of the device can be reduced.

In the above embodiment, the arm 2a is fixed, and the intermediate arms 2b, 2c and the outer arms 2d, 2e are moved to change the pitch of the semiconductor wafer 1. For example, one of the outer arms 2d, 2e is used. May be fixed and the other arm may be moved. Further, the present invention is not limited to the semiconductor wafer 1 and can be used for transporting any plate-like body such as a glass substrate for a liquid crystal display. Further, the number of arms for supporting the plate-like body is not limited to five, but may be any number such as 25.

As described above, the arm drive mechanism using the pinion and the rack made of hard resin generates less metallic dust and oily dust,
Since the pinion and the rack are also hard resins, dust generation can be extremely reduced. The material of the rack and the pinion is not limited to a hard resin, but may be a metal such as stainless steel.

[Effects of the Invention] As described above, according to the plate-shaped body transporting device of the present invention, it is possible to reduce the amount of generated dust and reduce the height of the device as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a main part of an embodiment of the present invention, FIG. 2 is a top view of FIG. 1, and FIG. 3 is a diagram showing an entire configuration of the embodiment of the present invention. 1 ... Semiconductor wafer, 2a ... Center arm, 2b, 2c ... Intermediate arm, 2d, 2e ... Outer arm, 3 ... Linear slider, 4 ... Arm support part, 5 ... Round bar, 6, 7 ... pulley, 8 ... belt, 9 ... motor, 10 ... rotating shaft, 11
… Pinion for outer arm, 12… Pinion for middle arm, 13b, 13c… Rack, 14d, 14e… Rack.

Claims (1)

(57) [Claims] 1. A plate-like body transporting device in which a plurality of arms for supporting a plate-like body are arranged so that said plate-like bodies are substantially parallel to each other at equal intervals. In the plate-shaped body transport device configured to be able to change the body interval, a first arm provided at a center among the plurality of arms is fixed, and a first arm provided at both sides of the first arm is provided. The second arm is driven by a rack disposed on the second arm and a first pinion provided so as to mesh with the rack so as to be translated in opposite directions to each other. The third arms provided on the outside each have a rack disposed on the third arm and a second arm having twice the number of teeth of the first pinion provided to mesh with the rack. Translated in opposite directions by the pinion To as being driven, the plate-like body conveying apparatus characterized by being configured to change the spacing of the plate-like body.