JPS6186311A - Plate-like material transfer device - Google Patents

Abstract

PURPOSE:To prevent wafers from being contaminated by dust, in a wafer transfer device utilizing an air bearing, by providing a cover member on the top surface of the body of the device to seal up a transfer path against the outside air. CONSTITUTION:A cover member 22 is removably attached to the guide walls 10a, 10b of a transfer path for a wafer 20 to seal up the transfer path against the outside air. In this arrangement air A is charged under pressure through air feed passages 16, 18 in order to transfer the wafer 20, and therefore the wafer is held in air by jetted air from oblique jet holes 16a, 18a to be advanced. The stream of air is shielded against the outside air by means of the cover 22 so that it is possible to prevent dust from entering into the stream of air, thereby it is possible to prevent the wafer from being contaminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a wafer transfer device that utilizes the air bearing effect. For example, regarding air bearings used in the manufacture of semiconductor integrated circuits, Japanese Patent Application Laid-Open No. 51-3
No. 7484.

Conventionally, a wafer is constructed by providing a large number of air injection holes on the top surface of the main body to transfer the semiconductor wafer in a predetermined direction using the air bearing effect, and with guide walls arranged on both sides of the transfer path on the top surface of the main body to guide the transfer of the wafer. A transfer device has been proposed. This type of equipment is useful because it allows semiconductor wafers to be transferred in a predetermined direction without touching the semiconductor wafer by human hands or special equipment, but in conventional equipment of this type, the transfer path is open to the outside air. Because
There is a drawback that dust in the air and dust on the wafer are blown up by the ejected air and adhere to the wafer again, contaminating it.

An object of the present invention is to provide a new dust-proof wafer transfer device that eliminates such drawbacks.

One of the features of the present invention is that exhaust grooves are provided on both sides of the wafer transfer path to prevent blowing air from being rolled up, and another feature is that the wafer transfer path is sealed from the outside air with a cover member. Another feature is that a forced exhaust hole is provided at the exhaust port to compensate for the reduction in transfer speed caused by sealing the transfer path and to exhaust air from the exhaust groove. By following these features, it is possible to prevent dust from adhering to the wafer without reducing the wafer transfer speed, thereby realizing clean air bearing transfer. In other words, dust in the air is prevented by installing the cover member,
The dust attached to the wafer and blown away by the ejected air is forced out through the exhaust hole to the outside of the transfer path. Moreover, if you simply install a cover member,
As the pressure in the transfer path increases, the transfer speed decreases, but
In the present invention, the airflow is actively enhanced by forced exhaust, so that the transfer rate is increased rather than decreased.

Other features and advantages of the present invention will become more apparent from the following description of preferred embodiments of the invention with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view perpendicular to a transfer path of a wafer transfer device according to an embodiment of the present invention, and FIGS. 23 and 2b are longitudinal cross-sectional views along the transfer path. In these figures, 10
1 is an apparatus main body, and a large number of air injection holes 16a+18a are formed on the upper surface of the apparatus in order to transfer the semiconductor wafer 20 in a predetermined direction by an air bearing effect. The air ejection holes 16a, 18a each communicate with an air supply passage 16.18 extending inside the main body along the transport direction.

, guide walls 10a are provided on both sides of the wafer 20 transfer path.

10b are arranged respectively to guide the transfer of the wafer 20. These guide walls 10a.

A cover member 22 is removably attached to the upper part of 10b to seal the transfer path from outside air.

Further, dust collecting grooves 24 and 26 are formed along the inner sides of the guide walls 10a and 10b, respectively, and these grooves 24.
On the bottom of each of the holes 16a, there is a spout hole 16a along the transfer path.
, 18a are provided with a large number of exhaust holes 12a, 14a having angles opposite to those of the exhaust holes 12a, 14a. These exhaust holes 12a and 14a each form an exhaust path 1 extending along the transfer path within the main body 10.
2, '14. The dust collection grooves 24 and 26 are provided to further increase the dust collection effect, and do not necessarily have to be provided, in which case the exhaust holes 12a, 1
4a is provided on the same plane as the ejection hole 15aT182.

In the operation of the device having the above configuration, the air supply path 16.
Air A is pressurized into 18 as shown by the arrow, and the exhaust path 1
2.14 is forcibly evacuated by pulling a vacuum ■ as shown by the arrow. Then, the wafer 20 is transported while being held in the air by air jetted from the jetting holes 16a and 18a, which are tilted in the forward direction. Then, the ejected air is sucked into the exhaust holes 12a and 14a and exhausted.

The reason why the exhaust holes 12a and 14a are formed with an inclination opposite to that of the jetting holes 16a + 18a with respect to the advancing direction of the wafer 20 is that the jetting air is drawn in and exhausted in an arcuate trajectory. This is to further promote the advancement of the wafer 20.

In the above operation, the presence of the cover member 22 prevents dust from entering from the outside air, and also prevents the wafer 2 from entering.
Dust attached to the 0 is also removed by the air cleaner effect. Therefore, clean wafer transfer is possible. Furthermore, since the transport air flow is actively melted by forced exhaust, high-speed wafer transport is possible.

Although the apparatus of the present invention is particularly useful for automatically transferring semiconductor wafers where dust adhesion is extremely difficult, it is needless to say that the application is not limited thereto, and may be used for other wafer-like objects (e.g., for semiconductor wafer exposure). It is clear that it can also be effectively used for transporting masks, thick film substrates, thin film substrates, etc.).

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a wafer transfer apparatus according to an embodiment of the present invention, and FIGS. 2a and 2b are longitudinal cross-sectional views of the transfer path of the apparatus shown in FIG. Explanation of symbols 1O...Main body, 12.14...Exhaust path, 16.18
...Air supply path, 20...Wafer, 22...Cover member, 24.26...Dust collecting groove.

Claims (1)

[Claims] 1. In order to transfer the plate-shaped object in a predetermined direction by the air bearing effect, multiple rows of air jet holes are provided along the transfer path, and in order to guide the transfer of the plate-shaped object, there are holes on both sides of the transfer path on the top surface of the main body. What is claimed is: 1. A plate-shaped object transferring device comprising guide means disposed in each of said plate-shaped object transferring devices, wherein a cover member is disposed above the upper surface of said main body.