JPS59121226A - Air bearing - Google Patents

Abstract

PURPOSE:To contrive an improvement in reliability and productivity of a semiconductor device by preventing powder of wafer from being transferred to a processing chamber, by preventing an edge part of the wafer from damaging by providing a plurality of gas blow-off openings on wall surfaces of the inside of side walls of a transferring path. CONSTITUTION:Gas blow-off openings 16 are provided on the sides of a transferring path side of side walls 15 on both sides of an air bearing 11 and gas is made to blow off against the sides of a body 12 to be transferred, through which the body 12 to be transferred is prevented from bringing into contact with the side walls 15. It means that when the body 12 to be transferred approaches the right side wall 15, it is pushed away to the other side by the gas from the right blow-off opening 16 and then when the body 12 approaches the left side wall 15, the body 12 is pushed away to the other side contrary to the above. Although the body 12 to be transferred, therefore, repeats zigzag motion, it does not happen that the body 12 hits against the side wall 15. Lifting and transferring of the body 12 to be transferred are performed by the blow-off gas from a blow-off opening 13 provided on a floor surface 14 as usual. Wafer, therefore, can be transferred without damaging the same and reliability and productivity of the device can be improved in a production process of a semiconductor device.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to an air hair ring, and more particularly to a high-precision air bearing capable of conveying with improved straightness.

(2) Background of the technology Air bearings are a floating type (non-contact type) transportation method using fluid that is currently used in many fields, and it keeps the transported object in a non-contact state and prevents it from being damaged. Therefore, it is particularly suitable for transporting items such as wafers and masks that need to be protected from being scratched on their front or back surfaces. In addition, air bearings are useful for automating the sifting of articles, and are therefore increasingly being incorporated into semiconductor devices.

Figure 1 is a diagram to explain the conventional air hair ring.
In the same figure, fat is a partial perspective view, and (bl is a cross-sectional view taken along the line A-A in the above fal. The gas outlet 3 is regularly arranged in the conveyance path 4.The gas outlet 3 is located diagonally forward in the general feeding direction as shown in the same figure (bl). The gas is arranged so that the gas can be blown out, and the gas supplied from a supply device (not shown) passes through the supply channel 3a connected thereto and reaches each outlet 3.
It is blown out from.

Due to the above-mentioned gas blowout, the conveyed object 2, such as Ueno\, rises from the floor of the conveyance path 4, and is pushed forward by the forward pressure of the gas, and the conveyed object 1ift is thus regularly Blowout from the gas blowout port 3 provided at
It floats up due to gas pressure and is transported smoothly without contact.

(3) Regarding conventional technology and problems, in the conventional air bearing mentioned above,
As shown by the solid arrow in fat in the same figure, it has been experienced that the conveyed object 2 makes a zigzag movement and comes into contact with the side wall 5, causing damage to its edge portion. As a result, fragments and powder caused by damage to the carrier such as wafers are carried to the processing chamber together with the carrier, and during the processing of the carrier, the above-mentioned debris and powder (15) adhere to the carrier and cause trouble. A problem has arisen.

(4) Purpose of the Invention In view of the above-mentioned conventional problems, an object of the present invention is to provide a high-precision air bearing that can perform conveyance with good linearity.

(5) Structure and object of the invention According to the present invention, in an air bearing in which a gas outlet is disposed on the conveying road floor surface and side walls are provided on both sides of the conveying path, the wall surface of the side wall on the conveying path side This is achieved by providing an air bearing characterized by having a gas outlet disposed in the air bearing.

(6) 6 examples of actual inventions Embodiments of the present invention will be explained in detail below with reference to the drawings.

FIG. 2 (al is a perspective view of the embodiment of the present invention, and FIG. 2 fb is a cross-sectional view taken along line B-B in FIG. .

Referring to the same figure, in addition to the gas outlet 13 on the conveyance road floor surface, the air steering ring 11 is provided with a gas outlet 16 on the sides of the side walls 15 on both sides facing the conveyance path. By blowing out the IM toward the side surface of the conveyed body 12, the conveyed body 12 is prevented from coming into contact with the side wall 15. That is, when the conveyed object 12 approaches the right side wall 15 as seen in FIG.
Next, when approaching the left side wall 15, in the opposite direction from the front (
The conveyed object thus repeats the zigzag movement in a similar manner as in the prior art, but never hits the side wall 15. Note that lifting and conveying of the conveyed object 12 is performed by blowing gas from an outlet 13 disposed on the floor surface 14 as in the conventional manner.

The supply of the blowing gas from the blowing outlet 16 is carried out through the conveyance path 1.
If a supply system separate from the gas supply system to the outlet 13 disposed at 4 is provided, gas control can be easily performed. Such a separate gas supply system (not shown)
In order to reliably prevent the object from coming into contact with the side wall 15, in addition to the gas supply, the amount of blown gas is also adjusted depending on the type of object to be transported. In other words, in the case of a transported object whose side surface facing the side wall 15 has a small area (thin thickness), the amount of gas is increased to increase the pressure applied to the side surface of the transported object, and conversely, the side surface area is increased. If the amount is large, the amount of gas is reduced to prevent the object to be transported from touching the side wall 15, thereby achieving effective linear transport.

The above-mentioned adjustment of the gas amount can be achieved by a normal technique using a regulator or the like (not shown) depending on the type of object to be transported. Furthermore, the position and dimensions of the gas outlet 16 are also set appropriately depending on the type of object to be transported.

In addition to the gas supply system described above, it is also possible to supply gas with a single gas supply system, and in this case, adjusting the gas supply amount requires a more complicated mechanism than in the case described above. Even so, the gas amount can be adjusted using normal techniques.

(7) Consequences of the Invention As explained in detail above, according to the present invention, it is possible to provide an air bearing with improved straightness in which the conveyed object does not touch the side wall. In the manufacturing process, for example, wafers or masks are coated with Bi (
Since the wafer can be transported without M, and wafer powder and debris are prevented from being carried into the processing chamber together with the wafer, it is highly effective in improving the reliability and productivity of semiconductor devices.

[Brief explanation of drawings]

Figure 2 is a diagram to explain a conventional air bearing.
Figure +a+ is a perspective view of the main part, Figure (b) is a sectional view thereof, Figure 2 (al is a perspective view of the main part of the embodiment of the present invention, Figure (b) is a perspective view of the main part,
+ is a sectional view taken along line 13-B in the same figure (al). 1.11- air bearing, 2.12- conveyed object, 3
．． 13.16-Gas outlet 3a--Gas supply pipe, 4.1
4-Conveyance road surface 5.15-Side wall Fig. 1 Fig. 2

Claims (1)

[Claims] An air hair ring having a plurality of gas outlets on a conveyance path surface and side walls provided on both sides of the conveyance path, the plurality of gas outlets being arranged on the wall surface of the side wall on the side of the conveyance path. Air bearings are characterized by: