JP2998687B2 - Brush scrub equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a cleaning device,
In particular, the present invention relates to a brush scrub apparatus which is suitable for cleaning a semiconductor substrate or a liquid crystal substrate.

[0002]

2. Description of the Related Art Recently, in a semiconductor manufacturing process, a CMP (Chemical Mechanical) is used to planarize an interlayer insulating film surface by, for example, increasing the number of layers of logic wiring.
l polishing (chemical mechanical polishing) is being adopted. Also, CMP technology is being introduced into memories such as DRAMs.

[0003] By the way, on the wafer surface after the CMP, various contaminants, in particular, many abrasive particles including silica are present. For the purpose of removing various contaminants adhering to the wafer surface, brush scrub cleaning using a chemical such as acid or alkali is performed.

FIG. 3 shows a main configuration of a brush scrubber cleaning unit generally used as a post-CMP cleaning (post-CMP cleaning) technique.

Referring to FIG. 3, brushes 4 and 4 ′ are provided on both front and back sides so as to sandwich the wafer 1 (dual).
On the upper side of the brush 4, a chemical solution supply nozzle 3 is provided. A wafer rotating mechanism 2 for rotating the wafer 1 is provided at an edge portion of the wafer 1. The wafer 1 is rotated by rotating the wafer rotating mechanism 2. At this time, brush 4,
At the same time as rotating 4 ', the cleaning liquid 6 is supplied from the chemical liquid supply nozzle 3, and both sides of the wafer are scrubbed.

Japanese Patent Application Laid-Open No. Hei 5-290373 discloses that
In performing a cleaning process on a plurality of disks by a batch processing method, a configuration of an apparatus for cleaning while adjusting a pitch interval to adjust to ultrasonic cleaning and brush cleaning stations having different disk pitch intervals has been proposed. ing. FIG. 5 shows a brush cleaning mechanism of this conventional apparatus.

Referring to FIG. 5, rotatable chuck members 52 are provided at three points on the outer periphery of the disk 51, whereby the disk 51 is rotatably supported. A rotating shaft 53 is provided on both sides of the plurality of disks 51.
A roll brush 54 made of a sponge or the like mounted on the disk 51 is brought into contact with the roll brushes 54 at both ends.
Are arranged so as to abut only on one side. A gear 59 is mounted on the other end of the rotating shaft 53. By rotating the motor 55, the pulley 56, the transmission belt 57,
The pulley 58, the driving gear 59, and the rotating shaft 53 rotate. The rotation of the rotation shaft 53 causes the rotation shaft 5 to rotate.
The entire surface of the disk 51 is cleaned while the roll brush 54 mounted on the disk 3 rotates.

[0008]

As described above, the CM
The wafer surface after P (chemical mechanical polishing) contains many contaminants, particularly a large amount of abrasive particles such as silica. These various contaminants cause problems in semiconductor manufacturing and device characteristics.

In the conventional brush scrub system shown in FIG. 4, the contaminants removed from the wafer are difficult to be discharged from the wafer because the wafer surface is horizontal, and the contaminants removed from the wafer surface tend to adhere again. Further, the throughput is low because of the single-wafer method.

The brush cleaning mechanism shown in FIG. 5 simultaneously cleans a wafer surface requiring a high degree of cleaning and a backside of a wafer requiring a low degree of cleaning with a single brush. As a result, the wafer surface is contaminated, and it is difficult to increase the degree of cleaning on the front side.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to reduce the number of particles remaining on the wafer surface and to brush-clean a large number of wafers at once. It is an object of the present invention to provide a cleaning apparatus which makes it possible to improve the throughput.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a cleaning apparatus for brush scrub cleaning of a substrate, wherein the surface of the substrate to be processed and the back surface thereof are placed face to face, and Substrates and brushes are alternately arranged.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. In a preferred embodiment of the cleaning apparatus of the present invention, a substrate to be cleaned (1 in FIG. 1)
For rotating the substrate (in a vertical or vertical direction) and rotating the substrate (wafer rotating mechanism 2 in FIG. 1), and a brush (a brush for abutting the substrate surface to perform scrub cleaning). 1) and a chemical liquid supply means (3 in FIG. 1) for supplying a cleaning liquid to the brush, so that a plurality of substrates to be cleaned have their front surfaces and back surfaces facing each other. A plurality of brushes are arranged vertically with respect to the arrangement of a plurality of substrates to be cleaned, between adjacent substrates, and with respect to substrates at both ends so as to be respectively applied to one surface of the substrate. By rotating each substrate, rotating each brush, and supplying a cleaning liquid (6 in FIG. 1) from above the brush from the chemical liquid supply means, brush scrubbing the front and back surfaces of a plurality of substrates at the same time. To do One in which the.

In the embodiment of the present invention, since the wafer is upright (the surface of the wafer is vertical), the removed contaminants effectively flow from below and are discharged from the wafer.

Further, in the embodiment of the present invention, since the front surfaces of the wafers or the back surfaces of the wafers having substantially the same degree of cleaning are cleaned, contaminants removed from the back surface of the wafer having a low cleaning degree are used. Contamination of highly cleaned wafer surfaces is completely avoided.

Further, in the embodiment of the present invention,
Since a large number of wafers can be brush-scrubbed at one time, the throughput is improved.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 is a view schematically showing a configuration of a brush scrub cleaning unit in a cleaning apparatus according to an embodiment of the present invention. FIG. 1A is a view of a plurality of wafers viewed from a side, and FIG. 1) is a view of the wafer surface as viewed from the brush side in contact with the wafer surface, that is, from the XX ′ direction in FIG.

Referring to FIG. 1, in the present embodiment,
It comprises a wafer rotating mechanism 2 that rotatably supports the wafer 1, a brush 4 for performing scrub cleaning, and a chemical supply nozzle 3 that supplies a cleaning liquid to the brush 4.
The wafer rotating mechanism 2 has a size and strength capable of holding the wafer 1 and has a circular shape for rotating the wafer 1. The wafer rotation mechanism 2 is driven to rotate by a motor (not shown) or a torque transmission mechanism and a speed reducer of the motor.

The brush 4 has a hardness suitable for cleaning the wafer 1, and the length of the brush 3 is slightly larger than the diameter of the wafer 1 (see FIG. 1 (b)). For example, PVA is preferable.

The chemical liquid supply nozzle 3 is provided with at least three chemical liquid discharge ports 5 each having a diameter of 1 mm to 5 mm for supplying a cleaning liquid to the brush 4, so that the cleaning liquid can be uniformly supplied to the entire brush 4. It has been like that. The material of the chemical supply nozzle 3 is preferably Teflon or quartz.

The wafer cleaning process using the cleaning apparatus according to the present embodiment will be described. Although not shown in FIG. 1, the wafer 1 transferred from the wafer inlet is located at the front of the brush scrub unit (unit). The front side and the back side of the wafer 1 are opposed to each other by the wafer refilling device provided in the above.

The wafers 1 and the brushes 4 transferred to the brush scrub section are alternately arranged, and the wafer 1 is rotated by a wafer rotating mechanism 2.
To be held. Then, the wafer 1 is rotated by rotating the wafer rotating mechanism 2. At this time, brush 4
Is rotated as shown in FIG.
The cleaning liquid 6 is supplied from the chemical liquid supply nozzle 3 provided at the upper part of the brush, and brush scrub cleaning is performed.

Although not shown, the cleaned wafer is transported to a wafer refilling device provided at the subsequent stage of the brush scrub section, the wafer surface is restored to its original orientation, and then transported to a wafer outlet. .

As a comparative example, using the above-described prior art shown in FIG. 4 and the present embodiment, after performing brush scrub cleaning with pure water for 1 minute, the particle diameter remaining on the wafer surface was 0.02 to 0.02.
FIG. 2 shows an example of a comparison of the number of particles of μm or more.

FIG. 2 shows that in the conventional technique, particles having a particle size of 0.02 μm or more remaining on the wafer surface are 77
It can be seen that while the brush scrubbing device according to the present embodiment is used, the number is reduced to 1/3 or less to 24.

An example of a comparison of the time required to process 25 wafers when brush scrub cleaning is performed for 1 minute using the above-described prior art shown in FIG. 4 and this embodiment as a comparative example. Is shown in FIG.

From FIG. 5, it can be seen that the conventional technique requires 27 minutes, whereas the brush scrubbing apparatus according to the present embodiment can perform the processing within 1/10 or less within 3 minutes.

In this embodiment, brush scrub cleaning of a semiconductor wafer has been described. However, the present invention can be applied to other brush scrub cleaning such as a liquid crystal substrate.

[0029]

As described above, according to the present invention, both sides of the wafer can be effectively cleaned as compared with the conventional brush scrub cleaning technique, so that the number of particles remaining on the wafer surface can be reduced. At the same time, since a large amount of wafers can be brush-scrub-cleaned at a time, there is an effect that the throughput can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a brush scrub cleaning apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a result of comparing the number of particles remaining on a wafer surface when brush scrub cleaning is performed using one embodiment of the present invention with a case where cleaning is performed by a conventional brush scrub cleaning apparatus. .

FIG. 3 shows the result of comparing the time required to process 25 wafers when brush scrub cleaning is performed using one embodiment of the present invention with the case where cleaning is performed using a conventional brush scrub cleaning apparatus. FIG.

FIG. 4 is a view for explaining a configuration of a conventional brush scrub cleaning device.

FIG. 5 is a view for explaining a configuration of a conventional brush scrub type disk cleaning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer 2 Wafer rotation mechanism 3 Chemical supply nozzle 4 Brush 5 Cleaning liquid discharge port

Claims (3)

(57) [Claims] 1. A cleaning apparatus for performing brush scrub cleaning of a substrate, wherein a plurality of substrates to be processed are placed with their front surfaces and back surfaces facing each other, and the upright processed substrates and brushes are alternately arranged. A cleaning device characterized in that: 2. A plurality of said substrates comprising: means for supporting a substrate to be cleaned in an upright state and rotating said substrate; and brushes for abutting said substrate surface to perform scrub cleaning. Are arranged vertically so that the front surface and the back surface face each other, and for the arrangement of a plurality of substrates, between the adjacent substrates,
A plurality of the brushes are arranged so that the substrates at both ends are respectively provided on one surface of the substrate, and the respective substrates are rotated, and the respective brushes are rotated. A scrub brush at the same time. 3. A chemical liquid supply means for supplying a cleaning liquid to the brush, comprising a chemical liquid supply nozzle provided above the brush along a longitudinal direction of the brush, wherein the chemical liquid supply nozzle is provided at a predetermined position in the longitudinal direction. 3. The cleaning apparatus according to claim 2, further comprising a plurality of chemical solution discharge ports separated from each other to perform cleaning from top to bottom.