JPH04348522A - Centrifugal dehydrator - Google Patents

Abstract

PURPOSE:To prevent dust floating in or deposited on a chamber from adhering to a semiconductor substrate. CONSTITUTION:An upper spray nozzle 7 for spraying pure water is provided in the vicinity of a swivel pin 3 of a cradle 1, and a lower spray nozzle 8 for spraying pure water is provided in the vicinity of a bearing unit of a rotating table 2. Every time drying work at a given time is carried out, cleaning work is carried out with the upper spray nozzle 7 and the lower spray nozzle 8.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal dehydrator in which a cassette containing a plurality of semiconductor substrates is attached to a rotating mechanism, and the semiconductor substrates are dehydrated by the centrifugal force of the rotation.

0002

2. Description of the Related Art FIG. 2 is a schematic cross-sectional view of a centrifugal dewatering machine, which is an example of the prior art. Conventionally, this type of centrifugal dehydrator has, for example, as shown in FIG. A table 2, a bearing part (not shown) that supports and holds the rotating shaft 4 of the rotating table 2, and a motor 5 that rotates the rotating shaft 4.
It had a chamber 9 and a lid 6 that covered the rotary table 2 including the clade 1.

When drying semiconductor substrates using this centrifugal dehydrator, first, a cassette 10 containing a number of wet semiconductor substrates 11 after washing with pure water is placed in a cradle 1.
Install. Next, the lid 6 is closed, and the rotary table 2 to which the cradle 1 is attached is rotated at high speed by the motor 5 for a certain period of time. As a result, the moisture attached to the semiconductor substrate 11 is shaken off by the centrifugal force caused by this high-speed rotation, and the semiconductor substrate 11 is dehydrated and dried. Next, the rotation of the motor 5 is stopped, and the dried semiconductor substrate 11 is taken out from the cradle 1 while being housed in the cassette 10.

This device is effective because it can dry a large number of semiconductor substrates in a very short time.

[0005]

[Problems to be Solved by the Invention] When this conventional centrifugal dryer is operated for a long period of time, dust is generated from the swinging mechanism by the rotatable pin of the cradle or the bearing of the rotary table, and dust is brought in from the outside. There is a problem in that the dust adheres, accumulates, and floats within the chamber, leading to the dust adhering to the semiconductor substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a centrifugal dehydrator in which dust does not adhere to semiconductor substrates in order to solve this problem.

[0007]

[Means for solving the problems] The centrifugal dehydrator of the present invention has the following features:
a cradle for mounting a cassette containing a plurality of semiconductor substrates; a rotary table for mounting the plurality of cradles via rotatable pins; a bearing section for supporting and holding a rotating shaft of the rotary table; The device includes a chamber and a lid for covering, a first spray nozzle for spraying pure water on the bearing portion, and a second spray nozzle for spraying pure water on the rotatable pin, and dehydrates the semiconductor substrate for a predetermined period of time. Each time the operation is performed, the first
The cleaning operation is characterized in that a second spray nozzle sprays pure water, and the rotary table is rotated to perform a dehydrating operation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a schematic sectional view of a centrifugal dehydrator showing an embodiment of the present invention. As shown in FIG. 1, this centrifugal dehydrator has an upper spray nozzle 7 which is attached to a lid 6 and sprays pure water onto a rotatable pin 3 of a cradle 1, and an upper spray nozzle 7 which is attached to a side wall of a chamber 9 and rotates. Lower spray nozzle 8 that sprays pure water on the bearing part of table 2
This is because we have established the following. Other than that, it is the same as the conventional example.

Next, the operation of this centrifugal dehydrator will be explained. As in the conventional example, after a certain period of drying operation, this centrifugal dryer automatically enters a device cleaning operation. First, cradle 1 should be empty, and rotary table 2 should be empty.
is rotated at, for example, 300 rpm, and at the same time pure water is sprayed from the upper spray nozzle 7 and the lower spray nozzle 8. In this state, the inside of the chamber 9 is being cleaned for 3 minutes. Then, after a predetermined period of time has elapsed, the sprinkling of pure water is stopped. Next, the rotary table 2 is rotated at 900 rpm for 3 minutes, for example, to dehydrate and dry the pure water adhering to the empty cradle 1 and the rotary table 2, and the cleaning operation is completed. Since this cleaning operation is repeated every drying operation for a certain period of time, it is possible to suppress the accumulation of dust in the chamber 1 and the rotating mechanism.The results of using this centrifugal dehydrator are compared with the results of using a conventional centrifugal dehydrator. After several weeks of use, the number of dust particles adhering to the conventional centrifugal dehydrator was reduced to about 5, compared to about 50 in the conventional centrifugal dehydrator, and a remarkable effect could be obtained.

[0011]

Effects of the Invention As explained above, in the present invention, the cleaning operation of spraying pure water on the swinging mechanism of the cradle and the bearing of the rotary table and dehydrating it by rotation is repeated every certain period of drying work. This has the effect of suppressing the accumulation of dust and providing a centrifugal dehydrator that reduces dust adhering to semiconductor substrates.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a centrifugal dehydrator showing one embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a conventional centrifugal dehydrator.

[Explanation of symbols]

1 Cradle 2 Rotary table 3 Rotatable pin 4 Rotation axis 5 Motor 6 Lid 7 Upper spray nozzle 8 Lower spray nozzle 9 Chamber 10 Cassette 11 Semiconductor substrate

Claims (1)

[Claims] 1. A cradle for mounting a cassette containing a plurality of semiconductor substrates, a rotary table for mounting the plurality of cradles via rotatable pins, a bearing section for supporting and holding a rotating shaft of the rotary table, the cradle and A chamber and a lid that surround and cover the rotary table, a first spray nozzle that sprays pure water on the bearing part, and a second spray nozzle that sprays pure water on the rotatable pin, and the semiconductor substrate for a predetermined period of time. A centrifugal dehydrator characterized in that each time the centrifugal dehydrator is operated to remove moisture, the first and second spray nozzles spray pure water, and the rotary table is rotated to perform a cleaning operation of dehydrating.