JPH06298361A - Wafer transfer device - Google Patents

Abstract

PURPOSE:To transfer a wafer in super-pure water without exposing it to the air, and transfer the wafer in a sheet shape without generating any super-pure water bacteria. CONSTITUTION:The super-pure water 2 is stored in a duct 1, and a wafer is placed on a float 4 immersed in the super-pure water. The float 4 holds the wafer 3 in the super-pure water 2, and its water part floats in the super-pure water. At the position of a wafer handling device 10, a stopper 6 stops the float 4 for wafer processing, and the wafer is placed on the float 4 again. When the stopper 6 is removed, the wafer is transfered in an arrow direction 5 together with the super-pure water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer transfer device.

[0002]

2. Description of the Related Art In recent years, with the high integration of devices, the quality required for wafers has become more and more severe. In order to deal with this, various measures are taken in wafer handling even in the wafer manufacturing process. Conventionally, when transferring a wafer, a wafer having a relatively small diameter such as 4 inches, 5 inches, 6 inches, or 8 inches has a diameter of 2 inches.
A method is adopted in which every five sheets are stored in a cassette and transferred to the next process.

When the wafer is dried and transferred to the next step,
Partial non-uniformity of drying and alteration of the wafer surface due to oxidation in the air occur. To prevent this, a technique of transferring the wafer to the next step while being immersed in ultrapure water has been developed. On the other hand, when the diameter of the wafer becomes large, for example, a wafer having a diameter of 8 inches and a wafer having a diameter of 12 inches are required next to the wafer. Therefore, the weight per sheet becomes heavy, and the single-wafer transportation is performed in order to prevent damage during transportation. preferable.

[0004] When carrying a wafer by immersing it in ultrapure water and carrying it, various carrying devices have been developed, but in any case, there are the following problems. (1) Management of ultrapure water is difficult, bacteria are likely to be generated, and wafer quality is adversely affected. (2) Since ultrapure water is scattered during the transportation, or is transported together with the ultrapure water, the weight becomes heavy and there is a limit to automation.

On the other hand, in the single-wafer transfer, a conveyor system in which a wafer is placed on a belt conveyor and transferred is generally used. However, since the conveyor and the like always have movable parts, particles adhering to the wafer surface are inevitable. Transportation in ultrapure water has various problems, such as being a major cause of dust generation in pure water, and has not been successful.

[0006]

In order to cope with the sophistication of the required quality of wafers and the enlarging of the wafer diameter due to the increase in the degree of integration of devices in the future, (1) single wafer transfer (2) ultrapure water Immersion transfer into the inside (3) Address management of wafers (4) It is necessary to supply appropriate wafers according to each facility capacity in the device manufacturing process.

[0007]

The present invention was developed to solve the above problems all at once. That is,
The present invention provides: (a) an ultrapure water circulation channel designed so that ultrapure water flows at a constant rate and a fixed volume. (B) Floating in ultrapure water even when a wafer is placed thereon A float for wafer transfer, whose buoyancy is adjusted so as to be immersed, is configured. Further, (c) it is preferable to include a position detecting sensor installed for wafer recognition, a position transmitting signal transmitter incorporated in the float, or the like.

[0008]

[Operation] When the float is put into the ultrapure water circulation passage,
When the wafer is placed, the float remains floating and the wafer is immersed in ultrapure water. The entire float can be easily moved in accordance with the flow of ultrapure water, and the float stopper can be used to stop the float at a fixed position to transfer the wafer in a predetermined process.

[0009]

EXAMPLES Examples are shown in FIGS. The ultrapure water 2 is stored in the channel 1 and is made to flow in the direction of arrow 5. The wafer 3 is placed on the float 4 immersed in the ultrapure water 2. The float 4 holds the wafer 3 in the ultrapure water 2 and
The whole is suspended in ultrapure water 2. At the position of the wafer handling device 10, the stopper 6 is shifted as shown by the arrow 7, the float 4 is stopped, the wafer handling device 10 is operated, the wafer is taken out and processed, and after the processing, it is placed on the float 4 again. When the stopper 6 is shifted to the outside, the wafer 3 is transferred together with the ultrapure water 2 in the direction of arrow 5.

[0010]

According to the present invention, the wafer can be transferred without exposing it to the air. Also, when transferring ultrapure water,
In order to maintain a constant flow velocity, ultrapure water does not generate bacteria and can be transferred as a single wafer.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a wafer transfer device according to an embodiment.

FIG. 2 is an explanatory diagram of a wafer transfer device according to an embodiment.

FIG. 3 is an explanatory diagram of a wafer transfer device according to an embodiment.

[Explanation of symbols]

 1 flow path 2 ultrapure water 3 wafer 4 float 5 arrow (flow direction) 6 stopper 7 arrow 10 handling device

Claims (1)

[Claims] 1. A circulating flow path containing ultrapure water, a drive source for causing the ultrapure water to flow in a certain direction, and buoyancy so that a wafer is immersed in the ultrapure water in a wafer mounted state. And a wafer transfer float that is adjusted.