JP2002109730A - Method and apparatus for magnetic disk transfer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease particle influence and improve contact in recording predetermined magnetic patterns on a magnetic disk with a magnetic transfer method. SOLUTION: A cleaning part 7, which removes particles entering from outside of an apparatus, is provided, and magnetic disk handling through a disk handler 4 is performed in a condition that the inner radius, on which magnetic transfer of the magnetic disk is not executed, is vacuum absorbed. This allows the magnetic disk to reduce particle adhesion and perform magnetic transfer in a vacuum absorbed state, improving reliability of the magnetic disk.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is written on the surface of a magnetic recording disk in a hard disk drive (HDD) using a magnetic film as a recording material, which is now mainstream as an external storage device of a computer. The present invention relates to a method and an apparatus for writing a servo signal for positioning a magnetic head for writing / reading data or specific data using a magnetic transfer technique.

[0002]

2. Description of the Related Art Conventionally, a magnetic disk is shipped in a state where no magnetic information is written therein, and is incorporated in an HDD device, and thereafter, magnetic information necessary for the HDD device is written.
In the HDD, a magnetic disk is magnetically partitioned into concentric tracks having a fixed width, and data is read and read while a head follows the track.
Write. The HDD detects a head displacement from a magnetic signal called a servo signal written on a track, and controls the head so as not to deviate from the track. This operation is called track servo.

However, in order to write servo signals precisely concentrically on a magnetic disk on which nothing is written, a device having a precise position control function is required, and a mechanism required for positioning is externally provided. In order to insert the HDD more, the work is done to prevent dust from entering the HDD.
This had to be done in a clean room. Also, it takes several tens of minutes to write servo signals on tens of thousands of tracks on one surface while performing precise alignment. As described above, it is necessary to perform this servo signal writing operation for each HDD in a clean room, and since a high-precision device is used, this is a major factor in increasing the manufacturing cost of the HDD.

A technique for transferring a servo signal pattern instantaneously by applying a magnetic field from the outside while closely attaching a special disk for magnetic transfer called a master disk having the above-mentioned servo signal pattern to the magnetic disk, and Equipment is being developed. This makes it possible to reduce the drive manufacturing cost and increase the track density (narrow the track width). However, since the magnetic transfer is performed while the master disk is brought into close contact with the magnetic disk, particles sandwiched between them cause a serious problem. In particular, particles often adhere to the outer peripheral portion while the magnetic disk is transported. The trapped particles deteriorate the adhesion between the master disk and the magnetic medium,
This results in quality deterioration of the transfer signal. These can be detected by signal evaluation, but there is a possibility that the master disk may be damaged by the interposed particles.
If the magnetic disk is an aluminum substrate, it has a certain degree of plasticity, so that damage to the master disk by particles does not cause much problem.

[0005]

However, if the magnetic disk is a hard glass substrate, the probability that the master disk will be damaged by particles increases, and at the same time, the magnetic film is broken by the relatively small particles on the magnetic disk side. It will cause serious damage. In addition, since the damage of such a magnetic disk is relatively narrow, there is a problem that it is difficult to detect the damage unless a precise inspection is performed in a test process. By the way, the particles include those coming from an external environment and those adhering to a medium (magnetic disk) to be transferred. The latter, which adheres to the magnetic disk, can be detected by optically inspecting the surface of the magnetic disk for foreign matter before the magnetic transfer step. However, the yield in this optical inspection cannot be increased unless the incoming particles themselves are reduced.

Conventionally, a magnetic disk cleaning process has been performed before the magnetic transfer process. However, this process uses a separate apparatus, and there is a risk that particles will adhere to the magnetic disk after the cleaning and during the magnetic transfer. Cannot be avoided sufficiently. Therefore, an object of the present invention is to reduce the influence of particles and improve the adhesion.

[0007]

According to the first aspect of the present invention, a master disk having a predetermined magnetic pattern is brought into close contact with a magnetic disk to apply a magnetic field from the outside, and the predetermined magnetic pattern is applied. In a magnetic disk transfer method for transferring a pattern onto a magnetic disk, it is preferable that after the back surface of the magnetic disk opposite to the magnetic transfer surface is handled by vacuum suction, an operation of removing particles adhering to the magnetic disk is performed. Features.

According to the first aspect of the present invention, an optical test can be performed between the removal of the particles and the magnetic transfer to determine whether or not the particles are attached (the second aspect of the invention). . These claims 1
In the invention of the second aspect, the magnetic disk may be a glass substrate magnetic disk.

According to a fourth aspect of the present invention, there is provided a magnetic disk transfer device for transferring a predetermined magnetic pattern onto a magnetic disk by applying a magnetic field from outside by bringing a master disk having a predetermined magnetic pattern into close contact with the magnetic disk. The magnetic disk is characterized in that handling means for vacuum-sucking the back surface opposite to the magnetic transfer surface of the magnetic disk and particle removing means for removing particles adhering to the magnetic disk are provided.

[0010] In the fourth aspect of the present invention, it is possible to arrange a test means for optically testing whether or not the particles are attached between the particle removal by the particle removal means and the magnetic transfer (claim). Item 5). Further, in the invention according to claim 4 or 5, the magnetic disk can be a glass substrate magnetic disk (the invention according to claim 6).

[0011]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a magnetic disk transfer device, 2 is a cassette stage (entrance), 3 is a cassette stage (exit), 4 is a disk handler, 5 is a disk holding / feeding mechanism, 6 is a vacuum suction head, and 7 is a cleaning. , 8 a foreign matter inspection unit, 9 a magnetic erase unit, 10 a magnetic transfer unit, 11 a disk cassette, and 12 a magnetic disk.

In such a configuration, the magnetic disk 1
2 are usually put into the disk cassette 11 by 25 sheets, and are conveyed to the cassette stage 2 which is the transfer apparatus input port by the conveyor of the production line. The cassette stage 2 has a mechanism for pushing the disks up from the gap below the cassette, and raises the magnetic disks 12 one by one to the upper part of the disk cassette 11. The disk handler 4 has an inner peripheral chucking mechanism, inserts the chucking mechanism in a closed state on the inner periphery of the protruded magnetic disk 12, and then holds the magnetic disk 12 by opening the chucking mechanism.

The disk handler 4 holding the magnetic disk 12 rotates 180 degrees in the horizontal direction and 90 degrees in the vertical direction.
The magnetic disk thus held is mounted on the disk holding / feeding mechanism 5 inside the magnetic disk transfer device 1 by the rotation operation. The transfer operation of the magnetic disk mounted on the disk holding / feeding mechanism 5 is performed in the transfer device 1 in four stages as illustrated in FIG. Disk holding /
The feed mechanism unit 5 is constituted by combining six arms having a vacuum suction head 6 for vacuum-holding and holding the inner peripheral portion of the disk at the front end thereof at an equal angle, and is held by one vacuum suction head 6. The four-stage transfer operation is sequentially performed on the magnetic disk 12 while the disk holding / feeding mechanism 5 makes one rotation on a horizontal plane. The remaining two stages are used for loading and unloading the magnetic disk.

The above-described transfer operation is performed in four steps of cleaning, foreign substance inspection, magnetic erasure and magnetic transfer. For the magnetic disk 12 held by the disk handler 4 on a surface different from the magnetic transfer surface, the cleaning unit 7 performs a cleaning process on the magnetic transfer surface. As the cleaning process, there is a so-called tape cleaning system in which the tape is brought into contact with the medium surface to remove particles. By such a cleaning process, particles near the outermost peripheral portion, which do not cause a problem particularly when a normal magnetic disk is used but cause a problem in magnetic transfer, are removed.

Next, the magnetic disk is optically inspected by a foreign substance inspection unit 8 to determine whether or not particles adhere to the magnetic transfer surface of the magnetic disk 12. As a result of this inspection, the magnetic disk 12 that has been determined to be free of particles that pose a problem in magnetic transfer should be magnetically erased on the magnetic transfer surface in the magnetic eraser 9 and then transferred in the magnetic transfer unit 10. It is brought into close contact with a master disk having a magnetic pattern, and magnetic transfer processing is performed. The magnetic disk 12 that has completed the magnetic transfer is transferred by the disk handler 4 to the disk cassette 11 waiting on the cassette stage 3 for exit. By the foreign matter inspection unit 8,
The magnetic disk 12 that is determined to have particles that cause a problem in magnetic transfer is skipped by the magnetic erasing process and the magnetic transfer process and discarded as a defective disk.

FIG. 2 shows a structural example of the vacuum suction head 6 provided in the disk holding / feeding mechanism 5. That is, the vacuum suction head 6 has a circular shape having a diameter slightly larger than the inner diameter of the magnetic disk 12, and has the suction air port 13. The suction air port 13 is in a state in which air is drawn, and the inner pressure of the magnetic disk 12 is brought into close contact with the magnetic disk contact surface 14 of the suction portion by the negative pressure.

FIG. 3 shows a magnetic transfer step. Magnetic transfer is performed in two stages: magnetic erasure and magnetic pattern transfer for bringing the master disk 17 into close contact. Magnetic erasure is shown in FIG.
As described above, the entire surface is erased by rotating the erasing external magnet 15 once while keeping a fixed distance on the magnetic disk 12. Magnetic pattern transfer is as shown in FIG.
With the master disk 17 in close contact with the magnetic disk 12, the transfer external magnet 16 having a magnetic field in a direction opposite to that in the erase operation is
This is also performed by making one rotation while maintaining a constant distance.

FIG. 4 shows a magnetically transferred pattern. The magnetic pattern area 18 to be transferred has an effective innermost diameter 19 and an outermost diameter 20, and no effective pattern is transferred inside or outside the innermost diameter 19 and outermost diameter 20. FIG. 5 shows a configuration example of the master disk. As shown, a transfer magnetic pattern 21 is formed on the surface of the master disk 17. The transfer magnetic pattern 21 is usually formed in a pattern having a width of about 1 μm. It is necessary that the magnetic transfer process be performed while maintaining the adhesion. If a particle of about several μm is interposed here, a glass substrate having no particular plasticity may have a size of several mm to several tens mm.
Over the range described above.

[0019]

According to the present invention, the handling of the magnetic disk is performed by vacuum-sucking the back surface opposite to the surface to be magnetically transferred, so that particles are easily attached to the magnetic disk in the apparatus. The chucking operation of the inside diameter or the outside shape can be eliminated. In addition, by providing a mechanism inside the magnetic transfer device that cleans the particles that adhere in the process before entering the transfer device, it is less susceptible to particles from outside the device and particles that adhere to the inside of the device. Excellent magnetic transfer becomes possible.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is an external perspective view showing an example of a vacuum suction head.

FIG. 3 is an explanatory view of a magnetic transfer step.

FIG. 4 is an explanatory diagram of a magnetic transfer pattern.

FIG. 5 is an explanatory diagram showing a configuration example of a master disk.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetic disk transfer apparatus, 2 ... Cassette stage (entrance), 3 ... Cassette stage (exit), 4 ... Disk handler, 5 ... Disk holding / feeding mechanism part, 6 ... Vacuum suction head, 7 ... Cleaning part, 8 ... Foreign matter inspection section, 9: magnetic erasing section, 10: magnetic transfer section, 11: disk cassette, 12: magnetic disk, 13: suction port air port, 14
... Suction part magnetic disk contact surface, 15 ... Erase external magnet,
16: External magnet for transfer, 17: Master disk, 18:
Transfer magnetic pattern area, 19: Effective innermost diameter of transfer magnetic pattern, 20: Effective outermost diameter of transfer magnetic pattern, 21:
Transfer magnetic pattern.

Claims (6)

[Claims] 1. A magnetic disk transfer method in which a master disk having a predetermined magnetic pattern is brought into close contact with a magnetic disk and a magnetic field is externally applied to transfer the predetermined magnetic pattern onto the magnetic disk. A method of transferring a magnetic disk, comprising: after handling the back surface opposite to the surface by vacuum suction, removing particles adhering to the magnetic disk. 2. The magnetic disk transfer method according to claim 1, wherein an optical test is performed to determine whether or not the particles are attached between the time when the particles are removed and the time when the magnetic transfer is performed. 3. The method according to claim 1, wherein the magnetic disk is a glass substrate magnetic disk. 4. A magnetic disk transfer device for bringing a master disk having a predetermined magnetic pattern into close contact with a magnetic disk and applying an external magnetic field to transfer the predetermined magnetic pattern onto the magnetic disk. A magnetic disk transfer device, comprising: a handling means for vacuum-sucking the back surface opposite to the surface; and a particle removing means for removing particles adhering to the magnetic disk. 5. The magnetic device according to claim 4, wherein a test unit for optically testing whether or not the particles are attached is disposed between the particle removal by the particle removal unit and the magnetic transfer. Disk transfer device. 6. The magnetic disk transfer device according to claim 4, wherein the magnetic disk is a glass substrate magnetic disk.