WO2013125938A1

WO2013125938A1 - An apparatus for cleaning a substrate

Info

Publication number: WO2013125938A1
Application number: PCT/MY2013/000031
Authority: WO
Inventors: Kien Hui Liang; Kae Jeng Ng
Original assignee: Invenpro (M) Sdn Bhd
Priority date: 2012-02-21
Filing date: 2013-02-21
Publication date: 2013-08-29
Also published as: MY160764A

Abstract

The present invention relates to an apparatus (100) for cleaning a substrate by scrubbing off contaminants from the surface of the substrate. This apparatus (100) is designed for use in cleaning substrates of various materials, such as aluminum, plastic, ceramic, glass, and the like, which are the primary materials for fabricating the platters of a hard disk drive (HDD). The apparatus (100) of the present invention comprises a disc shifter (110) positioned at the top portion for indexing operation, a plurality of brushes (150) positioned at the middle portion for scrubbing operation, and a disc holder (120) positioned at the bottom portion for holding and spinning a disc-shaped substrate (160).

Description

AN APPARATUS FOR CLEANING A SUBSTRATE

TECHNICAL FIELD

The present invention relates generally to an apparatus and method for cleaning a disc-shaped substrate, and more particularly, to an apparatus and method for cleaning disc-shaped substrate for data storage device and optical media, such as hard disk drives (HDD), and the like.

BACKGROUND OF THE INVENTION

It is known in the art of computer technology that digital data storage is classified into primary storage and secondary storage. Primary storage is the storage that directly accessible by the central processing unit (CPU) and is also known as a memory. The CPU continuously reads instructions stored in the memory and executes them. Primary storage are volatile, they lose information stored within memory blocks when the computer is powered down. Secondary storage differs from primary storage, they are non-volatile and are not directly accessible by the CPU. Data permanently stored in secondary storage are transferred to the CPU via input / output channel of the computer's motherboard. In modern computers, secondary storage usually refers to hard disk drives (HDD). Hard disk drives typically have several hard disk platters / platters mounted on the same spindle inside the hard disk drives in which it is used for storing data.

Platters, CD, DVD, and BD are fabricated using disc-shaped substrates, primarily the materials of aluminum, plastic, glass, or ceramic. In the fabrication of platters, CD, DVD, and BD, the surfaces of the disc-shaped substrates are typically coated with a thin layer of magnetic or optical materials. During pre-coating process, disc-shaped substrates have to be cleaned to create a substrate free from any contaminants. Contaminants such as dust, pollen, hair, or smoke, introduced during critical stages of manufacturing can cause defections to the final product. Therefore, it is necessary to use disk scrubber during substrate preparation stage to clean the substrates.

Prior art U.S. patent no. 6,625,835 B l introduces a disk cascade scrubber for cleaning disk-shaped substrates, including silicon wafers such as used in the fabrication of semiconductors, and aluminum, ceramic, plastic, glass and multi-component disks for data storage devices. This scrubber apparatus incorporates a series or cascade of substrate preparation zones in a single unit. The advantages of this scrubber apparatus is that it can be configured for one or more parallel operations providing a continuous and multi-substrate operation that results in cleaner and more thoroughly prepared substrates in shorter period of time. The apparatus includes two pairs of rollers to prepare the substrate in a vertical orientation. A track is provided to support the substrate in vertical orientation between the two pairs of rollers, and a pair of guiding rollers is provided to move the substrate in the vertical orientation along the track between the two pairs of rollers. The apparatus further includes two pair of brushes oriented horizontally and arranged longitudinally from each other, and configured to receive in between the pairs of brushes a vertically oriented substrate. Nozzles are mounted above and on either side of the substrate, and configured to dispense cleaning fluids, such as DI water or chemicals onto both surfaces of the vertically oriented substrate. Simultaneously, the pairs of brushes are rotating and scrubbing off any contaminants on both surfaces of the substrate.

As this scrubber apparatus is using a chain track to move the substrate, it is not suitable for submerged scrubbing, as the movement of the chain track will create contaminations. Therefore, it is required to include a pair of nozzles for dispensing cleaning fluids and it creates complexity in designing and building the scrubber apparatus. Another disadvantage is the use of flat belt to rotate the substrate in which it only has a single point of contact with the substrate. In this case, slippage might occur and said substrate may not be properly rotated.

Hence, in order to address these issues, an apparatus for cleaning a disc-shaped substrate, which is also suitable to be used in either submerged or non-submerged scrubbing with simplified mechanical design, should be developed. SUMMARY OF THE INVENTION

In order to overcome the problems as mentioned above, the present invention aims to provide an apparatus, which has simpler mechanical structure, and a method to effectively remove contaminants of a disc-shaped substrate in a cost and time saving approach.

The apparatus of the present invention can be used during substrates preparation process for scrubbing off contaminants from the surfaces of the substrates. The apparatus is suitable for use in cleaning substrates of various materials, such as aluminum, glass, and the like, which are the primary materials for manufacturing the platters inside a hard disk drive (HDD).

The apparatus of the present invention is able to remove contaminants from the surface of a substrate in either a submerged or a non-submerged condition. Also, the apparatus of the present invention incorporates a plurality of scrubbing stations in series in a single unit for providing a continuous and multi substrates operation so that a plurality of substrates can be prepared in shorter period of time, and minimize transfer time from one to another scrubbing station.

According to the present invention, an apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) by using brushes (150), comprising a disc shifter (1 10) having a plurality of rollers (1 1 1);

a disc holder (120) having a plurality of rollers (121 );

a scrubbing section having a first and second rotating shafts (130, 140) positioned in between the disc shifter (1 10) and the disc holder (120);

a plurality of brushes (150) coupled to the first and second rotating shafts (130, 140) for removing contaminants;

wherein said rollers (1 1 1) of the disc shifter (1 10) are spaced at a predetermined length to fit in the disc-shaped substrate (160);

wherein said rollers (121 ) of the disc holder (120) are spaced at a predetermined length to fit in the disc-shaped substrate (160); wherein said disc shifter (1 10) is horizontally movable in reciprocal directions; and

wherein said scrubbing section is divided into a plurality of scrubbing stations. According to one embodiment of the present invention, the disc shifter (1 10) does the indexing of the disc-shaped substrate (160) when receiving the same from the brushes (150). At least two pairs of brushes (150) are oriented horizontally and arranged longitudinally from each other for receiving in between the pairs of brushes (150) a vertically oriented disc-shaped substrate (160). Upon receiving said disc-shaped substrate (160), the pairs of brushes (150) will rotate in a direction where the discshaped substrate (160) sits on a pair of rollers (121 ) of the disc holder (120) and subsequently initiates the scrubbing operation. The first and second rotating shafts (130, 140) then reverse the rotational direction so that the pairs of brushes ( 150) move the disc-shaped substrate (160) to sit on a pair of rollers (1 1 1) of the disc shifter (1 10). Subsequently, said disc shifter (1 10) moves in horizontal direction for transferring said disc-shaped substrate (160) into the next two pairs of brushes (150) of the next scrubbing station.

According to another embodiment of the present invention, the disc shifter (1 10) is preferably positioned on the top portion of the apparatus (100) so that the apparatus (100) can be partially or fully submerged into a cleaning fluid tank (170). Major benefits of this design are to simplify the mechanical design of the apparatus (100) and minimizing contamination and particle generated by the scrubbing process.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 shows a perspective view of an apparatus in accordance with the present invention;

Figure 2 shows a perspective view of an apparatus partially submerged in a cleaning liquid tank in accordance with the present invention; Figure 3 shows an axial view of an apparatus partially submerged in a cleaning liquid tank in accordance with the present invention;

Figure 3a shows an axial view of an apparatus in operational mode in accordance with the present invention;

Figure 3b shows an axial view of an apparatus in operational mode in accordance with the present invention; Figure 4a shows a front view of an apparatus in operational mode in accordance with the present invention;

Figure 4b shows a front view of an apparatus in operational mode in accordance with the present invention;

Figure 4c shows a front view of an apparatus in operational mode in accordance with the present invention;

Figure 4d shows a front view of an apparatus in operational mode in accordance with the present invention;

Figure 4e shows a front view of an apparatus in operational mode in accordance with the present invention; and Figure 4f shows a front view of an apparatus in operational mode in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Described below are preferred embodiments of the present invention with reference to the accompanying drawings. Each of the following preferred embodiments describes an example in which an apparatus (100) and method for cleaning a disc-shaped substrate (160) improves over existing prior art.

The cleaning liquid as described in the present invention refers to treated water such as pure water, ultra-pure water, reversed osmosis water, de-ionized water, a chemical solution or any other appropriate liquid.

The configuration of the invention is not limited to the modules mentioned in the following description.

Described herein is an apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) during disc fabrication process. Referring to Figures 1 to 3, the apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) according to an embodiment of the present invention comprises a scrubbing section. The scrubbing section is where a disc-shaped substrate (160) for scrubbing will be placed. The scrubbing section comprises a first and second rotating shafts ( 130, 140) and a plurality of brushes (150) is coupled to the first and second rotating shafts (130, 140). The scrubbing section is divided into a plurality of scrubbing station and each scrubbing station is configured to have at least two pairs of brushes (150) oriented horizontally and arranged longitudinally with each other for receiving in between the pairs of brushes (150) a vertically oriented disc-shaped substrate (160). The rotational movement of the first and second rotating shafts (130, 140) is reversible and opposes each other in order to allow the two pairs of brushes (150) to move the disc-shaped substrate in upward and downward directions.

Still referring to Figures 1 to 3, the apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) according to an embodiment of the present invention comprises a disc shifter (1 10) and a disc holder (120). The disc shifter (1 10) is horizontally movable in reciprocating directions. The disc shifter (110) is to index the disc-shaped substrate (160) by moving the disc-shaped substrate (160) from one scrubbing station to another scrubbing station. The disc shifter comprises a plurality of rollers (1 1 1 ) spaced in a predetermined length for receiving the discshaped substrate (160). The rollers (1 1 1) are coupled to the disc shifter (1 10) via rotating rods ( 1 12). During indexing operation, the first and second rotating shafts (130, 140) will rotate in a direction so as to allow the two pairs of brushes (150) to move the disc-shaped substrate (160) towards the rollers (1 1 1) and spins by the rollers (1 1 1). Subsequently, the disc shifter (1 10) moves horizontally until it reaches the next scrubbing station.

The disc holder (120) is to station the disc-shaped substrate (160). The disc holder

(120) comprises a plurality of rollers (121) spaced in a predetermined length for receiving and spinning the disc-shaped substrate (160). The rollers (121) are coupled to the disc holder (120) via rotating rods (122). During operation, the first and second rotating shafts (130, 140) will rotate in a direction so as to allow the two pairs of brushes (150) to receive and move the disc-shaped substrate (160) towards the rollers

(121) and sits on them. The rollers (121) rotate in one direction to spin the discshaped substrate (160) so as to allow the two pairs of brushes (150) to fully scrub off contaminants from the surface of the disc-shaped substrate (160).

Still referring to Figures 1 to 3, the apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) according to an embodiment of the present invention, said disc shifter (110) is preferably positioned on the top portion of the apparatus (100). One benefit of having the present mechanical structure design is that the apparatus (100) is partially or fully submerged inside a cleaning liquid tank (170). The disc holder (120) is positioned outside of the cleaning liquid tank (170) and the rotating rods (122) extend from the disc holder (120) into the cleaning liquid tank (170). The disc shifter (1 10) is positioned outside and above the cleaning liquid tank (170) and is preferably at the position that allows the rollers (1 1 1) to be partially submerged inside the cleaning liquid tank (170). This structure design allows the discshaped substrate (160) to be fully submerged inside the cleaning liquid tank (170) during scrubbing and indexing operations. Figures 3a and 3b show the operation mode of moving the disc-shaped substrate ( 160) upward and downward. Table 1 below shows the relationship between the rotational direction of the first and second rotating shafts (130, 140) and the movement direction of the disc-shaped substrate (160). First rotating shaft Second rotating shaft Disc-shaped substrate (130) (140) (160)

Clockwise Counter-clockwise Move downward

Counter-clockwise Clockwise Move upward

Table 1 : Relationship between rotational direction and movement direction.

Figures 4a to 4f show the apparatus (100) for removing contaminants from the surface of a disc-shaped substrate (160) in accordance with the present invention in operational mode. During operation, the disc-shaped substrate (160) to be cleaned is carried by a mechanical arm (not shown) into the first scrubbing station of the scrubbing section and is secured in a vertical position by the two pairs of brushes (150), while sits on top of a pair of rollers (121). The pair of rollers (121) starts to spin the disc-shaped substrate (160) and at the same time, the first and second rotating shafts (130, 140) start to rotate the brushes (150) in the downward direction so as to scrub off contaminants from the surface of the disc-shaped substrate (160) and to push down the disc-shaped substrate (160) onto the pair of rollers (121) in order to continuously spin the disc-shaped substrate (160). Simultaneously, the disc shifter (1 10) moves horizontally and aligns the first pair of rollers (1 1 1) to the first scrubbing station in preparation for the indexing operation.

After a predetermined period of time, the first and second rotating shafts (130, 140) change the rotational direction in order to lift up the disc-shaped substrate (160) towards the pair of rollers (11 1) of the disc shifter (1 10). Upon touching the rollers ( 11), the rollers (11 1) start to rotate and continuously spin the disc-shaped substrate (160) and continue with the scrubbing process. At the same time, the disc shifter (1 10) moves horizontally for returning to the original position so that the disc-shaped substrate (160) is now aligned with the next scrubbing station. Subsequently, the first and second rotating shafts (130, 140) change the rotational direction in order for the brushes (150) to pull down the disc-shaped substrate (160) towards the rollers (121) of the disc holder (120). These processes conclude one cycle of the scrubbing process and indexing process. The cycle of scrubbing process and indexing process is repeated infinitely until the disc-shaped substrate (160) reaches the final scrubbing station and will be removed from the scrubbing section by another mechanical arm (not shown). A summary then of what has been hereinbefore described by way of example of the present invention is an apparatus (100) for cleaning a substrate by scrubbing off contaminants from the surface of the substrate. The apparatus (100) is designed to be used by substrates of various materials, such as aluminum, glass, and the like, which are the primary materials for fabricating the platters inside a hard disk drive (HDD). Said apparatus (100) comprises a disc shifter (1 10) having a plurality of rollers (1 1 1), a disc holder (120) having a plurality of rollers (121), a scrubbing section having a first and second rotating shafts (130, 140) positioned in between the disc shifter (1 10) and the disc holder (120), and a plurality of brushes (150) coupled to the first and second rotating shafts (130, 140) for removing contaminants.

In as much as the present invention is subject to many variations, modifications and changes in detail, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Claims

1. An apparatus (100) for removing contaminants from the surface of a discshaped substrate (160) by using brushes (150), comprising:

a disc shifter (1 10) having a plurality of rollers (1 1 1) coupled to it; a disc holder (120) having a plurality of rollers (121) coupled to it; a scrubbing section having a first and second rotating shafts (130, 140) positioned in between the disc shifter (1 10) and the disc holder (120);

a plurality of brushes (150) coupled to the first and second rotating shafts (130, 140) for removing contaminants from the surface of a disc-shaped substrate;

wherein the rollers (1 1 1) of the disc shifter (1 10) are spaced at a predetermined length to fit in the disc-shaped substrate (160);

wherein the rollers (121) of the disc holder (120) are spaced at a predetermined length to fit in the disc-shaped substrate (160); and

wherein the disc shifter (110) is horizontally movable in reciprocating directions.

2. The apparatus (100) in accordance with claim 1, wherein the plurality of rollers (1 1 1) is coupled to the disc shifter (1 10) via rotating rods (1 12).

3. The apparatus (100) in accordance with claim 1 , wherein the plurality of rollers (121) is coupled to the disc holder (120) via rotating rods (122).

4. The apparatus (100) in accordance with claim 1 , wherein the rotational movement of the first and second rotating shafts (130, 140) is reversible.

5. The apparatus (100) in accordance with claim 1, wherein the rotational movement of the first and second rotating shafts (130, 140) opposes each other.

6. The apparatus (100) in accordance with claim 1 , wherein at least a pair of brushes (150) from the first rotating shaft (130) and at least a pair of brushes (150) from the second rotating shafts (140) forms a scrubbing station.

7. The apparatus (100) in accordance with claim 1 , where the apparatus ( 100) is partially submerged in a cleaning liquid tank (170).

8. The apparatus (100) in accordance with claim 1 , where the apparatus (100) is fully submerged in a cleaning liquid tank (170).

9. The apparatus (100) in accordance with claim 1 , wherein the scrubbing section is divided into a plurality of scrubbing stations.

10. The apparatus (100) in accordance with claim 9, wherein the disc-shaped substrate (160) is inserted into the first scrubbing station by a mechanical arm.

1 1. The apparatus (100) in accordance with claim 9, wherein the disc-shaped substrate (160) is removed from the final scrubbing station by a mechanical arm.

12. The apparatus ( 100) in accordance with claim 1 , wherein the rollers ( 1 1 1 ) of the disc shifter (1 10) rotate for spinning the disc-shaped substrate (160).

13. The apparatus (100) in accordance with claim 1 , wherein the rollers ( 121 ) of the disc holder (120) rotate for spinning the disc-shaped substrate (160).

14. A method of removing contaminants from the surface of a disc-shaped substrate ( 160) by using the apparatus (100) claimed in claims 1 to 13, comprising the steps of:

inserting the disc-shaped substrate (160) into the first scrubbing station by a mechanical arm and said disc-shaped substrate (160) is secured in a vertical position by the two pairs of brushes (150) and sits on top of a pair of rollers (121 ) of the disc holder (120);

rotating the first and second rotating shafts (130, 140) in clockwise and counter-clockwise directions respectively for securing the disc-shaped substrate (160) on top of the rollers (121 ) and simultaneously, rotating the rollers (1 21 ) for spinning the disc-shaped substrate (160); moving the disc shifter (1 10) horizontally and aligning the first pair of rollers ( 1 1 1) to the first scrubbing station where the disc-shaped substrate is currently undergoing cleaning process;

changing the rotational directions of the first and second rotating shafts (130, 140) for lifting the disc-shaped substrate (160) towards the disc shifter

(1 10) and securing the disc-shaped substrate (160) onto the pair of rollers

(i n);

rotating the rollers (1 1 1 ) for continuing spinning the disc-shaped substrate (160) and simultaneously, moving the disc shifter (1 10) horizontally for returning to the original position so that the disc-shaped substrate (160) is now aligned with the next scrubbing station; and

changing the rotational directions of the first and second rotating shaft (130, 140) to move the disc-shaped substrate (160) towards the disc holder ( 120) and rests on the rollers (121), and simultaneously, rotating the rollers (121) for continuing spinning the disc-shaped substrate (160).

15. The method in accordance with claim 14, wherein the method of removing contaminants from the surface of a disc-shaped substrate (160) is repeating infinitely so as to transfer the disc-shaped substrate (160) from one scrubbing station to another scrubbing station.

16. The method in accordance with claim 14, wherein the apparatus (100) is partially submerged in a cleaning liquid tank (170).

17. The method in accordance with claim 14, wherein the apparatus (100) is fully submerged in a cleaning liquid tank (170).

18. The method in accordance with claim 14, wherein the disc-shaped substrate (160) is removed from the final scrubbing station of the scrubbing section by a mechanical arm.